CCL2 and diabetes mellitus: CCL2 is a secreted factor expressed during normal immune surveillance, as well as in response to injury or infection. It influences a variety of tumors and diseases, including atherosclerosis, multiple sclerosis, and diabetes. Furthermore, CCL2 plays a critical role in the immune system by attracting immune cells to adipose tissue through chemotaxis, which is vital for macrophage infiltration into adipose tissue.