The Significance of the Intestinal Microbiome for Vaccinology: From Correlations to Therapeutic Applications

Despite unprecedented advances in understanding the intestinal microbiome, its potential to improve fields such as vaccinology has yet to be realized. This review briefly outlines the immunologic potential of the intestinal microbiome for vaccinology and highlights areas where the microbiome holds specific promise in vaccinology. Oral rotavirus vaccine effectiveness in low-income countries is used as a case study to describe how the intestinal microbiome may be employed to improve a vaccine’s immunogenicity. A top-down, evidence-based approach is proposed to identify effective microbiota-based applications for vaccine improvement. Applying evidence from field studies in pertinent populations that correlate microbiome composition with vaccine effectiveness to appropriate experimental platforms will lead to the identification of safe, vaccine-supporting microbiota targets that are relevant to populations in need of improvement in vaccine-induced immunity.