IL2 and systemic lupus erythematosus: The broad application of Ld-IL2 therapy is considered to be underpinned by the multiple mechanisms of its action, not only boosting the function of regulatory T (TREG) cells [31] to strengthen immune tolerance and homeostasis but also suppressing effector IL-17-producing helper T (TH17) [32] and follicular helper T (TFH) cells [33–35] to ameliorate inflammation and autoimmunity in lupus patients [30,36].