Regenerating islet-derived 3 gamma (REG3G), also known as pancreatitis-associated protein 1B (PAP1B), is a member of the secreted Reg superfamily and contains one typical C-type lectin domain. REG3G is expressed weakly in pancreas, strongly in intestinal tract, but not in hyperplastic islets REG3G might be a stress protein involved in the control of bacterial proliferation. It was indicated that REG3G specifically targets Gram-positive bacteria because it binds to their surface peptidoglycan layer, and serves as one of several antimicrobial peptides produced by paneth cells via stimulation of toll-like receptors (TLRs) by pathogen-associated molecular patterns (PAMPs).