REG1B (regenerating family member 1 beta) functions as a secretory protein involved in cellular proliferation, tissue regeneration, and host defense mechanisms. The protein demonstrates growth factor activity and is significantly upregulated during inflammatory and pathological conditions 1. REG1B expression is induced by IL-22 in intestinal epithelial cells, where it contributes to antimicrobial host defense responses alongside other regenerating family members 1. In pancreatic cells, REG1B exhibits interdependent relationships with antioxidant enzymes, with altered expression affecting cellular proliferation and viability 2. The protein serves as a biomarker for multiple diseases, showing elevated circulating levels years before pancreatic cancer diagnosis 3 and Crohn's disease onset 4. In colorectal cancer, REG1B is highly expressed and associated with cell differentiation status, where its silencing inhibits proliferation, migration, and invasion while inducing G1-phase cell cycle arrest 5. Single-cell analysis reveals REG1B is primarily expressed in goblet cells during inflammatory bowel conditions 6. As a secretory protein with lectin-like properties, REG1B may function through autocrine or paracrine mechanisms to promote cellular regeneration and maintain tissue homeostasis 7.