Incorporation of RG1 epitope into HPV16L1-VLP does not compromise L1-specific immunity

Area of Science:

• Virology
• Immunology
• Vaccinology

Background:

• Human Papillomavirus (HPV) infection is a major global health concern.
• Current HPV vaccines target specific high-risk (hr) and low-risk (lr) HPV types.
• There is a need for broadly protective HPV vaccines.

Purpose of the Study:

• To evaluate the immunogenicity and efficacy of the candidate pan-HPV vaccine RG1-VLP.
• To compare RG1-VLP to licensed HPV vaccines (Cervarix® and Gardasil®).
• To assess cross-neutralization against various hrHPV types.

Main Methods:

• Rabbits were immunized with RG1-VLP or Cervarix® at varying doses.
• Mice were immunized with RG1-VLP combined with HPV18L1-VLP to mimic adolescent schedules.
• Antibody titers, neutralization capacity, and cross-protection against HPV challenge were measured.

Main Results:

• RG1-VLP induced comparable HPV16 neutralization and capsid-reactive antibody titers to licensed vaccines.
• 25 µg RG1-VLP demonstrated robust cross-neutralization against multiple hrHPV types.
• Dual vaccination with RG1-VLP and HPV18L1-VLP in mice showed HPV16 neutralization and cross-protection against hrHPV58.

Conclusions:

• RG1-VLP vaccination elicits potent HPV16 neutralization comparable to existing vaccines.
• The candidate vaccine demonstrates broad cross-neutralization against diverse hrHPV types.
• RG1-VLP holds promise as a pan-HPV vaccine, potentially effective with reduced immunization schedules.