Brief Communication; A Heterologous Oncolytic Bacteria-Virus Prime-Boost Approach for Anticancer Vaccination in Mice

Area of Science:

• Immunology
• Oncolytic Virus Therapy
• Cancer Vaccination

Background:

• Anticancer vaccination is a growing therapeutic strategy for cancers expressing common tumor antigens.
• Heterologous prime-boost vaccination using two viruses encoding the same tumor antigen sequentially primes and boosts antitumor immunity.
• Current clinical investigations utilize adenovirus (Ad) and Maraba virus (MRB) for this approach.

Purpose of the Study:

• To evaluate Listeria monocytogenes as an alternative priming agent in a heterologous prime-boost anticancer vaccination strategy.
• To compare the efficacy of a Listeria monocytogenes-MRB prime-boost strategy against the established Ad-MRB combination.

Main Methods:

• Sequential administration of Listeria monocytogenes encoding a tumor antigen followed by Maraba virus (MRB) for immune priming and boosting.
• Assessment of immune priming efficiency and therapeutic benefits of the Listeria monocytogenes-MRB strategy.
• Comparison with the established adenovirus-MRB prime-boost vaccination regimen.

Main Results:

• Listeria monocytogenes demonstrated comparable immune priming efficiency to adenovirus prior to MRB boosting.
• The heterologous Listeria monocytogenes-MRB prime-boost strategy provided superior therapeutic benefits compared to the Ad-MRB combination.
• Proof of concept for an oncolytic bacteria-virus prime-boost approach in anticancer vaccination was established.

Conclusions:

• Listeria monocytogenes can effectively replace adenovirus in a heterologous prime-boost vaccination strategy against cancer.
• The Listeria monocytogenes-MRB prime-boost approach offers enhanced therapeutic advantages over the Ad-MRB combination.
• This novel bacteria-virus prime-boost strategy warrants clinical investigation for anticancer vaccination.