Oncolytic Rhabdovirus Vaccine Boosts Chimeric Anti-DEC205 Priming for Effective Cancer Immunotherapy

Area of Science:

• Immunology
• Vaccinology
• Oncolytic Virology

Background:

• Prime-boost vaccination strategies using heterologous viral vectors are effective for maximizing antigen-specific immune responses.
• Adenovirus serotype 5 (Ad5) is clinically evaluated as a prime, but pre-existing immunity is globally prevalent.
• Oncolytic rhabdoviruses encoding tumor antigens elicit robust anti-cancer immunity and improve survival in preclinical models.

Purpose of the Study:

• To explore DEC205-targeted antibodies as an alternative priming agent for oncolytic rhabdovirus boosting.
• To evaluate a prime-boost strategy using anti-DEC205-ovalbumin (OVA) and oncolytic rhabdovirus-OVA.
• To assess the efficacy of this strategy in a B16-OVA tumor model.

Main Methods:

• Development of an anti-DEC205 antibody fused to ovalbumin (OVA) for prime vaccination.
• Administration of oncolytic rhabdovirus encoding OVA as a boost.
• Evaluation of antigen-specific immune response and survival in a murine B16-OVA tumor model.

Main Results:

• The anti-DEC205-OVA prime followed by oncolytic rhabdovirus-OVA boost induced a robust antigen-specific immune response.
• This prime-boost vaccination strategy significantly improved survival in the B16-OVA tumor model.
• The approach demonstrated potential as an alternative to Ad5-based vaccines.

Conclusions:

• Anti-DEC205 antibodies fused to cancer antigens are effective priming agents for oncolytic rhabdovirus-boosted cancer antigen responses.
• This strategy offers a viable alternative for patients with pre-existing immunity to adenovirus serotype 5.
• The findings support the development of novel cancer vaccine platforms.