This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Chen, S.-A. Articles by Lai, M.-D. Search for Related Content PubMed PubMed Citation Articles by Chen, S.-A. Articles by Lai, M.-D.

Induction of Antitumor Immunity with Combination of HER2/neu DNA Vaccine and Interleukin 2 Gene-modified Tumor Vaccine¹

Departments of Biochemistry [S-A. C., M-H. T., F-T. W., M-D. L.], Microbiology and Immunology [A. H., Y-L. C., H-Y. L.], Urology [T-S. T.], Radiation Oncology [H. W. C. L.], and Pathology [Y-T. J.], College of Medicine, National Cheng Kung University, 701 Tainan, Taiwan, and Graduate Institute of Microbiology, College of Medicine, National Taiwan University, 100 Taipei, Taiwan [C-L. H., L-H. H.], Republic of China

ABSTRACT

The therapeutic effects of both cytokine-secreting tumor vaccine and DNA vaccine were studied using mouse MBT-2 bladder cancer cells as a model. Cytokine-secreting MBT-2 cells were obtained by infecting cells with retroviral particles containing interleukin (IL) 2-, IL-4-, or granulocyte-macrophage colony-stimulating factor (GM-CSF)-expression vector. The MBT-2-IL-2 cells were not tumorigenic in syngenic C3H mice at all. Tumor formation decreased significantly for the MBT-2-GM-CSF cells. MBT-2-IL-2, -IL-4, and -GM-CSF cells were killed by irradiation and tested as tumor vaccines. The irradiated MBT2-IL-2 cells could complete protect mice from the growth of the preexisting tumor cells, and the immune memory lasted for 8 months. On the other hand, irradiated MBT-2-IL-4 and MBT-2-GM-CSF cells were less effective. When the loading tumor mass increased, all tumor vaccines lost protective effects. DNA vaccine encoding the tumor antigen neu was additionally tested to improve the therapeutic efficacy. Coinjection of 60 µg pSV-neu DNA was effective in enhancing the antitumor effects of MBT2-IL-2; however, DNA vaccine alone cannot prevent the progression of the preexisting tumor. Immunohistochemical analysis of tumor infiltrate revealed massive increase of CD4⁺ lymphoid cells in the group of mice treated with both DNA vaccine and IL-2-secreted tumor vaccine. Western blotting demonstrated the presence of anti-neu antibody in the serum from immunized mice. In contrast, combination of DNA vaccine and MBT-2-GM-CSF has no additive effect. The results indicate the combination of DNA vaccine and IL-2-secreting tumor vaccine can additionally improve therapeutic efficacy, and the efficacy is correlated with the increase of CD4⁺ T lymphocytes and anti-neu antibody.

This article has been cited by other articles:

				J. Kochling, S. A. Konig-Merediz, R. Stripecke, D. Buchwald, A. Korte, H. G. von Einsiedel, F. Sack, G. Henze, K. Seeger, B. Wittig, et al. Protection of Mice against Philadelphia Chromosome-positive Acute Lymphoblastic Leukemia by Cell-based Vaccination Using Nonviral, Minimalistic Expression Vectors and Immunomodulatory Oligonucleotides Clin. Cancer Res., August 1, 2003; 9(8): 3142 - 3149. [Abstract] [Full Text] [PDF]