Human Peptidase Inhibitor 16 (PI16) Protein

Background

Peptidase Inhibitor 16 (PI16), also known as PSPBP (prostate secretory protein binding protein), is a member of the peptidase inhibitor family that plays a role in regulating protease activity in various tissues, particularly in the cardiovascular, immune, and reproductive systems. PI16 is a secreted protein expressed primarily by stromal fibroblasts, prostate cells, and cardiac tissues, among others. It has been identified as an immunomodulatory molecule and a marker for fibroblasts, especially those involved in tissue remodeling processes. By modulating protease activity, PI16 indirectly influences extracellular matrix (ECM) composition and cellular signaling, contributing to processes like fibrosis, inflammation, and cardiac function. Given its tissue-specific expression and involvement in immune responses, PI16 has been the subject of studies focused on its roles in cardiovascular diseases, cancer, and immune regulation.