Osteopontin (OPN) is expressed in a range of immune cells, including macrophages, neutrophils, dendritic cells, microglia and T and B cells, with varying kinetics. OPN is reported to act as an immune modulator in a variety of manners. Firstly, it has chemotactic properties, which promote cell recruitment to inflammatory sites. It also functions as an adhesion protein, involved in cell attachment and wound healing. In addition, OPN mediates cell activation and cytokine production, as well as promoting cell survival by regulating apoptosis. The following examples are found.