How VLP Structural Insights from Cryo-TEM Helped Characterize the GARDASIL® Vaccine

Virus-like particle vaccines require analytical methods that go beyond confirming primary protein structure. Direct visualization can provide important evidence about VLP morphology, assembly, integrity, aggregation, and interactions within the final vaccine formulation.

Using Cryo-TEM to Characterize GARDASIL® VLPs

This case study describes how cryo-transmission electron microscopy was used to examine the four HPV L1 VLP serotypes in the GARDASIL® vaccine. Automated imaging and single-particle analysis provided complementary structural information while preserving the particles in a hydrated, near-native state. The study also examined antibody-decorated VLPs and particles adsorbed onto an aluminum-containing adjuvant.

What You’ll Learn in the Case Study

• Which VLP characteristics can be directly assessed with cryo-TEM
• How images reveal particle shape, assembly state, integrity, and aggregation
• How 3D reconstruction provides insight into HPV capsid organization
• What cryo-TEM showed about VLP morphology on aluminum adjuvant

Download the case study to review the cryo-TEM images, reconstructed HPV VLP structures, and the role of this orthogonal method in vaccine characterization, process development, and comparability assessments.