Potent Antitumor Activity of IL-2-Fc Fusion Proteins Through FcyR-Dependent Depletion of Regulatory T-Cells

摘要

Interleukin-2 (IL-2)-mediated expansion of cytotoxic CD8+ T-cells and natural killer cells has been successfully used in cancer immunotherapy. However, clinical use of IL-2 is complicated by dose-limiting toxicities and inevitable expansion of CD4+ CD25+ regulatory T-cells (Tregs). Previous attempts to overcome these limitations have focused on maximization of cytotoxic cell expansion, as exemplified by IL-2/anti-IL-2 immune complexes and IL-2 'superagonist' proteins. Here, we report potent and selective activity of engineered fusion proteins consisting of IL-2 and the antibody Fc region.