Trained immunity-based vaccines: A vision from the one health initiative

Trained immunity-based vaccines (TIbV or TRIMbV) represent a novel approach to combating infectious diseases. The innate immune system in animals, including humans, exhibits "memory-like" functions. Remarkably, the immunological mechanisms -both epigenetic and metabolic-) underlying this memory enables immune cells to develop defensive and protective outcomes against unspecific pathogenic infections. Under this context, the One Health initiative promotes integrative efforts to combat zoonotic (and anthropozoonotic) diseases, which is critical because 3 of 4 animal infections are transmitted to humans. Therefore, TIbV constitutes a potential affordable approach to control zoonotic pathologies, especially under pandemic scenarios. This review describes the state-of-the-art TIbV and their hurdles, opportunities, and prospects for the One Health initiative to prevent, control, and treat infectious diseases.