The role of bacterial cell wall dimers in the innate immune response (970.1)

Abstract

The innate immune system is the body’s first line of defense against pathogens. The innate immune system is triggered by pathogen associated molecular patterns (PAMPs) that are recognized by pattern recognition receptors (PRRs) such as Toll‐like receptors (TLRs) and Nod‐like receptors (NLRs). This research project focuses on providing a better understanding of how the innate immune system senses and responds to the presence of bacteria. Specifically, our group is interested in the relationship between Nucleotide‐binding oligomerization domain‐containing protein 2 (Nod2), an NLR protein found in the cytosol of mammalian host cells, and muramyl dipeptide (MDP), the smallest bacterial cell wall fragment known to elicit an immunological response. When Nod2 is mutated, the signaling pathway becomes disrupted and uncontrollable inflammation arises, leading to chronic inflammatory bowel disorders such as Crohn’s disease. In order to discover how to better treat these diseases, it is imperative to learn more about how Nod2 and MDP interact, a mechanism which is currently unknown. The Grimes Lab has previously shown that Nod2 binds to MDP in vitro; however, research suggests that a heightened immunological response may be elicited in a host if molecules containing multiple MDP’s are used, suggesting multivalency is at play. This project highlights my current research progress to synthesize a variety of novel MDP dimers to test for a multivalent interaction between Nod2 and MDP.