this isnt exactly a vaccine its more like prophylactic immunoinduction.

"toll like receptors"

https://pmc.ncbi.nlm.nih.gov/articles/PMC7173040/

https://www.sciencedirect.com/science/article/pii/S135964462...

https://link.springer.com/article/10.1186/s40364-022-00436-7

https://en.wikipedia.org/wiki/Toll-like_receptor