title: [Effect of Tumor Vaccine of EL-4 Cell Transduced with IL-12 Gene in C57BL/6 Mice]
abstract: In order to study the vaccine potency of gene-modified tumor cells, IL-12 express vector was constructed by using retrovirus. The vector was transfected into EL-4 thymic lymphoma cells and the effect of transfectant on anti-tumor immunity was investigated. The tumorigenicity of EL-4/IL-12 transfectant in syngeneic C57BL/6 mice was decreased significantly after implanted with EL-4/IL-12 transfectant compared with EL-4/Wt or EL-4/Neo groups (P < 0.001). The systemic protective immunity was induced against the challenge with EL-4/Wt (in 8/10 mice) after the rejection of EL-4/IL-12 in vivo experiment, a stronger CTL activity against EL-4/Wt cells and a weak killer activity against syngeneic Lewis lung carcinoma (LLC) cells were obtained in (51)Cr release assay. In vivo depletion analysis suggested that the decreased tumorigenicity mainly depended on CD4(+), CD8(+) and NK cells. Therapeutic vaccines with EL-4/IL-12 cells could retard the growth of established EL-4/Wt tumors significantly compared with those of EL-4/Neo (P < 0.005). These studies suggested that immunotherapy and gene therapy using IL-12 is effective in hematopoietic malignancy and IL-12 has prospects of application in human cancer treatment in the near future.
authors.affiliation: Department of Molecular Biology and Genetic Engineering, Institute of Oncology, Harbin Medical University, Harbin 150040, China.
authors.forename: Zhihua
authors.initials: Z
authors.lastname: Wang
authors.forename: Xixiong
authors.initials: X
authors.lastname: Kang
authors.forename: Kenzaburo
authors.initials: K
authors.lastname: Tani
authors.forename: Hidetoshi
authors.initials: H
authors.lastname: Sumimoto
authors.forename: Yukoh
authors.initials: Y
authors.lastname: Nakazaka
authors.forename: Shigetaka
authors.initials: S
authors.lastname: Asano