Novel human interleukin-2 (IL-2) muteins or variants thereof are provided. In particular, provided are IL-2 muteins that have an increased binding capacity for IL-2RP receptor and a decreased binding capacity for IL-2RΥc receptor, as compared to wild-type IL-2. Such IL-2 muteins are useful, for example, as IL-2 partial agonist and antagonists in applications where reduction or inhibition of one or more IL-2 and/or IL-15 functions is useful (e.g., in the treatment of graft versus host disease (GVHD) and adult T cell leukemia). Also provided are nucleic acids encoding such IL-2 muteins, methods of making such IL-2 muteins, pharmaceutical compositions that include such IL-2 muteins and methods of treatment using such pharmaceutical compositions.