IL2 and systemic lupus erythematosus: The administration of low-dose IL-2 (at variable doses, but usually <1-2 million IU/day) is indeed capable of increasing the number of circulating Tregs several fold,58 and its use has been explored in multiple clinical trials of immune-mediated disease,59,60 with positive results mostly in chronic graft vs. host disease and systemic lupus erythematosus.61