ΔR2* analysis confirmed that CHOL-PEG-SPIO-IL19 was present in the tumor region of tumor-bearing mice, whereas less signal was observed in mice treated with SPIO-IL19, CHOL-PEG-SPIO-isotype, or SPIO, as seen in the T2* concentration map (Fig. 8B). The gene discussed is IL19; the disease is neoplasm.