Fig. 3　The pancreatic-gut axis for the regulation of the microbiome. GP2, Reg, sPLA2, lipase, and trypsin are pancreatic secretory components regulating the pathobionts. These agents protect the epithelial barrier and activate anti-microbial peptides, playing a pivotal role in mucosal defense. Anti-GP2 auto-antibodies produced in IBD patients neutralize the activities of GP2 in the microbiome. Translocated bacteria stimulate immune cells, such as macrophages, causing inflammatory cytokine release. TNF enhances the expression of GP2 under inflammatory conditions.