Because high concentrations of IL2 stimulate effector T cells (42), we hypothesized that tumor-adjacent delivery of our RPE-mIL2 capsules caused increases in effector T cell (CD8+) activation, proliferation, and migration into the tumor space without stimulating regulatory T cells (Tregs) (CD4+CD25+FOXp3+). Here, FOXP3 is linked to neoplasm.