T-cell receptor on CD4+ T helper cells recognizing Glatiramer Acetate-Major Histocompatibility Complex class II complexes (TCR (GA-MHC II))

T-cell receptors (TCRs) on CD4+ T helper (Th) cells that recognize Glatiramer Acetate (GA) presented by Major Histocompatibility Complex (MHC) class II molecules are the primary mediators of the immunomodulatory effects of GA in multiple sclerosis (Arnon R, et al. Proc Natl Acad Sci U S A. 2004). Glatiramer acetate is a synthetic polypeptide mixture that mimics Myelin Basic Protein (MBP), a key autoantigen in the pathogenesis of MS. Upon administration, GA competes with MBP for binding to MHC class II molecules on antigen-presenting cells. The resulting GA-MHC II complex is recognized by these specific TCRs, which triggers the expansion of GA-reactive Th2 and Th3 cells rather than pro-inflammatory Th1 cells (Schrempf W, et al. Autoimmun Rev. 2007). These GA-specific regulatory cells cross the blood-brain barrier and, upon encountering MBP in the central nervous system, release anti-inflammatory cytokines such as IL-4, IL-10, and TGF-beta. This mechanism, termed bystander suppression, reduces the inflammatory environment and protects against demyelination and axonal loss. Consequently, these TCRs serve as the functional interface for redirecting the autoimmune response toward a neuroprotective phenotype (FDA Copaxone Label).

Other names

Glatiramer acetate-reactive T-cell receptorGA-specific TCRCopaxone-reactive TCRT-cell receptor on GA-specific Th2 cells

Glatiramer acetate binds to MHC class II molecules and is presented to specific T-cell receptors, inducing a phenotypic shift from pro-inflammatory Th1 cells to anti-inflammatory Th2/regulatory T cells that provide bystander suppression in the central nervous system (Schrempf W, et al. Autoimmun Rev. 2007; Arnon R, et al. Proc Natl Acad Sci U S A. 2004).