Final answer:
In Paneth cells of the healthy gut, pattern recognition receptors (PRRs) sense PG fragments (MDP) and activate NOD2 receptors, which induce the production of antimicrobial peptides (AMPs). Mutations in this pathway can lead to overgrowth of commensal bacteria and recurrent inflammatory responses, resulting in inflammatory bowel disease (IBD).
Step-by-step explanation:
In Paneth cells of healthy gut, pattern recognition receptors (PRRs) sense PG fragments (MDP), activates NOD2 receptor which induces production of antimicrobial peptides (AMPs). AMPs act as a barrier to prevent overgrowth of commensal bacteria. If there is a mutation in this pathway, it leads to overgrowth of commensal bacteria, leading to recurrent inflammatory response, resulting in inflammatory bowel disease (IBD).