Immunomodulatory biomaterials as a novel therapeutic platform for inflammatory bowel disease

Inflammatory bowel disease (IBD) is a chronic autoimmune condition of the gut caused by an inappropriate reaction towards commensal bacteria by immune cells that reside within the gut-associated lymphoid tissue. IBD is of rising concern due to increased global incidence with no outright cure. Patients have changeable response to standard therapeutic pathways that result in lifelong contact with healthcare systems. This narrative review aims to evaluate the therapeutic potential of immunomodulatory biomaterials for IBD as an alternative approach to current treatment options. A literature search was conducted using PubMed, Google Scholar and Web of Science databases. The primary aim was to identify pre-clinical, laboratory studies that investigated biomaterials in the presence of IBD models. Herein, we review the advent of biomaterials that demonstrate immunomodulatory capacity to directly alleviate chronic IBD pathology. We demonstrate the difference between natural and synthetic polymers as building blocks for biomaterials, such as hydrogels, microspheres and nanospheres, which can be functionalised based upon specific IBD inflammatory markers. Here, we assess examples of immunomodulatory biomaterials tested in IBD cellular, tissue and animal models as inflammation-targeted alternatives to current therapeutics. We also discuss the gaps for further research, from administration to scalability considerations to demonstrate the realistic use of immunomodulatory biomaterials for IBD in the clinic.