DBP(Vitamin D-binding protein) also known as GC is a member of the albumin gene family. DBP plays a crucial role in transporting vitamin D and its metabolites to target organs within the vitamin D endocrine system, essential for maintaining calcium homeostasis and bone health. DBP exhibits immunomodulatory properties, binding to leukocyte surfaces and enhancing immune responses. DBP is located in the extracellular space, primarily in the serum, where DBP interacts with various cell types, facilitating diverse cellular functions. DBP binds to chondroitin sulfate proteoglycans on cell membranes, which is vital for cell signaling and immune response modulation. DBP serves as a co-chemotactic factor for C5a, enhancing chemotactic activity, and has a high-affinity interaction with globular actin, contributing to actin clearance from the bloodstream.