Because of its strong immunomodulatory effect without increasing the risk of infection, IL-2 has been used in the treatment of type 1 diabetes and systemic lupus erythematosus, and its inherent mechanism is that low doses of IL-2 can promote the proliferation of Treg cells and restore the balance of immune system [12, 13]. Here, IL2 is linked to systemic lupus erythematosus.