Calgranulin is an S100 calcium-binding protein that is expressed in multiple cell types, including renal epithelial cells and neutrophils.
The proteins S100A8 and S100A9 form a heterodimer called calprotectin.
Some in vitro evidence suggests that calgranulin can inhibit the precipitation of calcium oxalate in a urine-like environment at calgranulin concentrations below physiological concentrations.[1] Thus, it may also function in vivo as an inhibitor of calcium oxalate kidney stone formation. However, the role of calgranulin in the stone formation process has not been evaluated.