Native-like Mayaro virus–like particles produced in mammalian cells elicit strong neutralizing antibodies and protect mice without adjuvant, offering a rapid, low-risk path to vaccine prototyping and benchmarking for alphavirus antigens.

Figure from Kim et al. (2024). License CC BY 4.0

What we studied

We examined recombinant Mayaro virus (MAYV) virus-like particles (VLPs) carrying E1–E2 glycoproteins and capsid produced in mammalian cells, and compared their structure and immunogenicity to alternative vaccine platforms and subunit antigens. Single-particle cryo-EM tested whether these VLPs present native-like spikes; mouse immunizations assessed functional neutralization and protection.

Key results

• Cryo-EM shows MAYV VLPs closely mimic native virion architecture, presenting natively assembled E1–E2 spikes.
• VLPs and viral-vectored E1–E2(+capsid) vaccines elicited highly neutralizing antibodies, outperforming soluble monomeric E2 antigen. Boosting further increased responses.
• Non-adjuvanted VLPs (single or two 5 µg doses) protected mice from viremia and MAYV-induced foot swelling, indicating adjuvant-free efficacy in this model.
• LC-MS confirmed E1/E2 glycosylation compositions consistent with characterized alphaviruses, supporting antigenic authenticity.

Why it matters

For organizations prioritizing rapid, low-risk vaccine prototyping, these data validate MAYV VLPs as a non-infectious, native-like antigen that induces strong neutralization and protection without adjuvant. Structurally faithful display plus robust in vivo readouts make VLPs a practical path to first-in-animal decision points and a benchmark for assessing other alphavirus VLPs.

Methods in brief

Single-particle cryo-EM of purified MAYV VLPs; viral-vectored comparators (Ad/MVA) expressing E1–E2(+capsid); mouse immunization and challenge; PRNT/VRP neutralization assays; LC-MS glycan profiling.

References

Kim YC, Watanabe Y, Lücke A-C, et al. Immunogenic recombinant Mayaro virus-like particles present natively assembled glycoprotein. npj Vaccines 9, 243 (2024). https://doi.org/10.1038/s41541-024-01021-9