T-cell receptor specific for pertussis-toxoid peptide–MHC II complex (PT-specific TCR)

The T-cell receptor (TCR) specific for pertussis-toxoid peptide–MHC II complexes is a specialized surface receptor found on CD4+ helper T cells that mediates the adaptive immune response to Bordetella pertussis. These receptors recognize specific peptide fragments derived from the pertussis toxoid (PT), a primary virulence factor and vaccine antigen, when presented by Major Histocompatibility Complex (MHC) class II molecules on antigen-presenting cells. Binding of the TCR to the PT-MHC II complex triggers intracellular signaling through the CD3 complex, leading to T-cell proliferation and the differentiation of effector cells that secrete protective cytokines like IFN-gamma and IL-17. This interaction is the fundamental mechanism by which acellular pertussis vaccines (aP) and whole-cell vaccines (wP) induce protective immunity. Monitoring these TCR-bearing cells is essential for understanding vaccine-induced protection and the phenomenon of waning immunity in populations immunized with acellular vaccines. Research into the TCR repertoire of these cells helps in identifying immunodominant epitopes for improved vaccine design.

Other names

Pertussis-toxoid specific T-cell receptorPT-specific T-cell receptorCD4+ T-cell receptor for pertussis toxoidTCR specific for PT-MHC II

Antigen-specific activation of CD4+ T cells via TCR-MHC II binding, leading to the orchestration of cellular and humoral adaptive immunity.