Myelin-derived peptide–MHC class II complex

The Myelin-derived peptide–MHC class II complex is a protein complex formed when peptides generated from myelin proteins (notably myelin basic protein, MBP) are loaded onto major histocompatibility complex class II (MHC II) molecules expressed by antigen-presenting cells[1][2][3][5][6]. These complexes are central to the activation of CD4+ T cells, mediating self/non-self-recognition in the central nervous system and shaping immune tolerance versus autoimmunity[3][5][6]. In multiple sclerosis and related demyelinating diseases, pathogenic CD4+ T cells recognize specific CNS myelin-derived peptides presented by MHC II, precipitating immune-mediated myelin damage[2][3][5][6]. The precise composition and structure of the complex (for example, MBP 89–101 segment bound to HLA-DR2a) determines which CD4+ T cell clones are activated or tolerized[2][3]. Targeting this complex—either by modulating MHC II peptide presentation, blocking pathogenic T cell recognition, or tolerizing the immune response—remains a central therapeutic goal in MS and autoimmune CNS disorders[3][5][6].

Other names

Myelin peptide–MHC II complexMyelin basic protein–MHC II complexMyelin antigen–MHC class II complexMBP–MHC II complex

Modulation of antigen presentation to T cells; Inhibition or redirection of autoreactive T cell activation; Immunomodulation of CNS antigen presentation; Induction of regulatory T cell responses