How do conjugate vaccines work?
In a conjugate vaccine, the weak antigen is covalently attached to a strong antigen, thereby eliciting a stronger immunological response to the weak antigen. Most commonly, the weak antigen is a polysaccharide that is attached to strong protein antigen.
Do conjugate vaccines stimulate B cells?
PS conjugate vaccines recruit CD4+ T cells via a carrier protein, such as tetanus toxoid (TT), resulting in the induction of PS-specific BMEM. However, the requirement for T cells in the subsequent activation of the BMEM at the time of bacterial encounter is poorly understood, despite having critical implications for …
Are conjugate vaccines T cell Dependant?
T-independent response | T-dependent response | conjugate vaccine | polysaccharide | Salmonella Typhi B acterial capsular polysaccharides (PSs) have been used for many decades as vaccines; however, their use has been limited due to the absence of immunogenicity in infants and young children, the lack of induction of …
Do conjugate vaccines elicit AB lymphocyte cell response?
Cells from mice immunized with any of the conjugates yielded vigorous T-cell responses to whole antigen. We conclude that the serotype of PnPS can alter the peptide specificities of T-cell responses, but even a poorly immunogenic PnPS conjugate can elicit a significant T-cell response.
What are examples of conjugate vaccines?
Examples include Haemophilus Influenza Conjugate Vaccine (Hib) and Pneumoccocal Conjugate Vaccine (Prevnar®).
What are the advantages of conjugate vaccines?
Further advantages of the conjugate vaccines are their ability to elicit immunological memory and to reduce asymptomatic carriage of the bacteria, resulting in marked herd immunity.
What is the purpose of conjugate vaccines?
Conjugate vaccines have been developed to induce a robust immune response against bacterial capsular polysaccharides (CPSs). CPSs are long polymers composed of many repeating units of simple sugars and serve as a protective external layer for many bacteria.
What are the contraindications for live vaccines?
A severe allergic reaction (e.g., anaphylaxis) to a vaccine component is a contraindication to any vaccine containing that component, and a severe allergy following a dose of vaccine is a contraindication to subsequent doses of that vaccine. Severe immunosuppression is a contraindication to live, attenuated vaccines.
Do conjugate vaccines have a T cell mediated response?
Therefore, with conjugate vaccines, T cells are engaged; they provide the help necessary to start the GC reaction that leads to affinity maturation, proliferation, and the production of plasma cells (which produce polysaccharide-specific antibodies) and memory B cells.
What is an example of a conjugate vaccine?
When is typhoid conjugate vaccine given?
Administer the first dose at age 15 through 18 months and the second dose at age 4 through 6 years. The second dose may be administered before age 4 years, provided at least 3 months have elapsed since the first dose.
What are some examples of conjugate vaccines?