Antibodies and B cell receptors directed against diphtheria toxoid or tetanus toxoid carrier protein epitopes

Antibodies and B cell receptors (BCRs) directed against diphtheria toxoid (DT) or tetanus toxoid (TT) are essential mediators of the immune response to many conjugate vaccines. DT and TT are chemically inactivated toxins that serve as potent carrier proteins, providing necessary T-cell epitopes to stimulate a robust B-cell response against poorly immunogenic antigens like bacterial polysaccharides (Pollard et al., 2009, Nature Reviews Immunology). Upon binding to these carrier epitopes, BCRs facilitate the internalization and presentation of the vaccine complex to T-helper cells, which is a prerequisite for high-affinity antibody production and immunological memory (Pichichero, 2013, Human Vaccines & Immunotherapeutics). In clinical settings, the concentration of antibodies against these toxoids is a standard measure for assessing a patient's immune competence and the success of immunization (WHO, 2017). However, the presence of high-titer pre-existing antibodies can lead to carrier-induced epitopic suppression, where the immune response to the conjugated antigen is diminished (Schutze et al., 1985, Journal of Immunology). These molecules are therefore central to the design, efficacy, and monitoring of a wide range of pediatric and adult vaccines.

Other names

Anti-diphtheria toxoid antibodiesAnti-tetanus toxoid antibodiesDiphtheria toxoid-specific B-cell receptorsTetanus toxoid-specific B-cell receptorsCarrier-specific B cellsAnti-DT IgGAnti-TT IgG

Binding of the B cell receptor to toxoid epitopes triggers receptor-mediated endocytosis, antigen processing, and presentation to T cells, leading to B cell differentiation into plasma cells and memory cells (Janeway et al., 2001, Immunobiology).