Recently, our group developed an HLA class I-positive NK feeder cell line originating from the adherent prostate carcinoma cell line PC3 and genetically engineered to express IL-2, 4-1BBL and a membrane-bound form of IL-15 (PC3PSCA-IL-2-4-1BBL-mIL-15d). The gene discussed is IL15; the disease is prostate carcinoma.