Haemophilus influenzae type b polyribosylribitol phosphate–tetanus toxoid conjugate (PRP-T (where PRP = polyribosylribitol phosphate; T = tetanus toxoid))

Haemophilus influenzae type b polyribosylribitol phosphate–tetanus toxoid conjugate is the active component of several Hib vaccines. It consists of the capsular polysaccharide (polyribosylribitol phosphate, PRP) of Haemophilus influenzae type b covalently linked to tetanus toxoid as a carrier protein. The PRP is a linear polymer of repeated units of β-D-ribofuranose and D-ribitol phosphate, which forms the main antigenic determinant of Hib. When conjugated to tetanus toxoid, the normally T cell–independent polysaccharide antigen becomes T cell–dependent, greatly enhancing immune response and antibody formation in infants and young children. This conjugate is not a receptor, enzyme, or endogenous molecular target but rather an immunogen (vaccine antigen) designed to elicit protective immunity against Hib infection[1][2][3][5][6][7]. Clarification: - This is not a classical molecular target such as a receptor, enzyme, or transporter. It is a conjugate vaccine antigen designed for immunization, not a druggable biological target. The entry as a “target” is incorrect; the canonical biological target would be the Haemophilus influenzae type b capsular polysaccharide (PRP), not the conjugate as provided. Note: - If seeking “target” data for drug discovery or mechanistic pharmacology, this conjugate is not suited as it fits the vaccine immunogen category[2][7]. - If you need structured information for databases focusing on therapeutic targets (receptors/enzymes/transporters), this entry is not appropriate and should be flagged as non-target. - For vaccine efficacy, the correlate of protection is anti-PRP IgG antibody level[5].

Other names

Haemophilus influenzae type b conjugate vaccineHib conjugate (tetanus toxoid conjugate)PRP-T vaccine

Induces anti-PRP IgG antibodies via T cell–dependent immune response when PRP is conjugated to a protein carrier (tetanus toxoid); induces long-term protective immunity against Hib infections[2][5][7].