Administration of IL-2 complexed to a specific IL-2 monoclonal antibody, JES6–1, is renoprotective in a mouse model of focal segmental glomerulosclerosis, according to new findings. Polhill et al. found that administration of the IL-2/IL-2 antibody complex to mice with adriamycin-induced nephropathy induced the expansion of T-regulatory cells and resulted in improved renal function, reduced inflammation, and reduced histologic injury. They suggest that administration of IL-2/IL-2 antibody complexes could expand T-regulatory cells and treat renal disease in humans.