Tremendous research endeavors have revealed a plethora of commensal-derived molecules that allow the microbiome to live harmoniously within the human host. Certain molecules have immunomodulating capabilities and protect the microbe by inducing immune tolerance instead of activation. If such molecules are also polymeric, they could be formulated into tolerogenic microparticles and offer new biomaterial-based strategies to combat inflammatory diseases, including allergy and autoimmunity. Envisioning commensal microbes as a source of novel biomaterials could revolutionize and enhance current immunotherapy strategies.