The role of microbe-associated molecular patterns and microbial metabolites on target cells for cellular therapy. The intestinal microbiota generates microbe-associated molecular patterns and metabolites, both of which play a pivotal role in modulating the functionality of immune cells as well as IECs, thereby influencing the outcome of cellular therapy. CDN, cyclic dinucleotides; ILA, indole-3-lactic acid; IPA, indole-3-propionic acid. Figure created with BioRender.com.