24 adult patients ( 18-55 years ) with established insulin-dependent type 1 diabetes and at least one diabetes-related autoantibody were enrolled and randomly assigned ( in a 1:1:1:1 ratio , by computer-generated randomisation list , with block size four ) to placebo or IL2 at 0.33 MIU/day , 1 MIU/day , or 3 MIU/day for a 5-day course and were followed up for 60 days .