Osteopontin is a key player for local adipose tissue macrophage proliferation in obesity

These data confirm that monocytes and macrophages not only are responsive to OPN and migrate to sites of inflammation but also they survive and proliferate more in the presence of OPN, a mechanism also strongly confirmed in vivo. Therefore, secreted OPN appears to be an essential player in AT inflammation, not only by driving monocyte chemotaxis and macrophage differentiation but also by facilitating local proliferation of macrophages.