Haemophilus influenzae type b capsular polysaccharide-tetanus toxoid conjugate (Hib PRP-T)

Haemophilus influenzae type b PRP-T conjugate is the active immunogenic component of certain Hib vaccines, consisting of the capsular polysaccharide polyribosyl ribitol phosphate (PRP) from Haemophilus influenzae type b, covalently linked to tetanus toxoid protein. The conjugation enhances immunogenicity by converting the polysaccharide into a T-cell dependent antigen, allowing infants and young children to mount an effective antibody response and develop immune memory. The PRP-T conjugate is not a target for drugs, but is used in vaccines (e.g., ActHIB, Hiberix) for the prevention of invasive Hib diseases in young children. Vaccination with Hib PRP-T conjugate has virtually eliminated Hib disease in immunized populations, though continued vigilance is necessary due to the potential for vaccine program lapses or waning immunity. As a vaccine component, Hib PRP-T is not a receptor, enzyme, or druggable molecular target, but rather an antigenic tool for prevention.

Other names

Haemophilus b conjugate (PRP-T) vaccineHib PRP-TPolyribosyl ribitol phosphate–tetanus toxoid conjugateTetanus toxoid–conjugated Hib vaccineHaemophilus influenzae type b conjugate vaccine (tetanus toxoid conjugate)

Induces a T-dependent immune response by presenting the Hib capsular polysaccharide (PRP) conjugated to tetanus toxoid, leading to antibody production (mainly IgG) and immune memory against Hib infection