What Immune memory is classically a hallmark of the adaptive immune response, however, emerging evidence shows that memory can also be induced in innate immune cells. We want to study whether and how the gut microbiome can induce such training of the innate immune system and investigate the long-term beneficial effects of such training during infection and inflammation. Why Dysregulation of the gut microbiome has been associated with multiple diseases both of the gastrointestinal tract and other organs, and such diseases are often associated with increased abundance and functional changes of specific innate immune cells. By studying the highly complex interplay between the microbiome and the innate immune system, we will establish knowledge which in the future can aid harness the microbiome-immune regulation. Long-term, the acquisition and utilization of such knowledge may serve as founding element for the advancement of established treatment forms and the development of novel therapeutic opportunities in multiple diseases. How Due to the complexity of the microbiome in both humans and mice, we will use mice models where we can accurately control the microbiome environment to perform this study. In order to investigate how the microbiome alters innate immune cells function we will use a cutting-edge single-cell multi-omics platform and analyse downstream transcriptomic and epigenetic landscape with different high-dimensional approaches. We will also use both models of inflammation and infection to inspect the long-term effects of training innate immune cells.