Glycoconjugate vaccines and immune interference: A review

Area of Science:

• Vaccinology
• Immunology
• Pediatric infectious diseases

Background:

• Bacterial polysaccharide-protein conjugate vaccines have transformed pediatric immunization.
• Commonly used carrier proteins include tetanus toxoid (TT), diphtheria toxoid (DT), and CRM197.
• DT conjugates are generally less immunogenic, while TT and CRM197 conjugates have specific drawbacks.

Purpose of the Study:

• To evaluate the immunogenicity and potential interference of different carrier proteins in conjugate vaccines.
• To identify limitations associated with current carrier proteins in pediatric vaccine strategies.
• To explore the need for novel carrier proteins to improve vaccine efficacy and combination potential.

Main Methods:

• Comparative analysis of immunogenicity data for Hib, pneumococcal, and meningococcal conjugate vaccines.
• Review of studies examining the impact of carrier proteins on polysaccharide responses.
• Assessment of 'bystander interference' phenomena in multivalent conjugate vaccines.

Main Results:

• Multivalent TT conjugates risk reduced polysaccharide responses.
• Multivalent CRM197 conjugates show lower risk of reduced polysaccharide responses but may cause bystander interference, impacting Hib and hepatitis B responses.
• DT conjugates generally exhibit lower immunogenicity.

Conclusions:

• Existing carrier proteins (TT, CRM197) have limitations impacting vaccine efficacy and combination strategies.
• Novel carrier proteins are needed to overcome current challenges and advance pediatric vaccine development.
• Further research into alternative carriers could lead to improved vaccine schedules and combinations.