Irradiated IL-2 gene-modified plasmacytoma vaccines are more efficient than live vaccines.
The effect of irradiation on the therapeutic efficacy of IL-2 gene-modified plasmacytoma cells used as a vaccine in the immunotherapy of parental murine plasmacytoma X63-Ag8.653 was examined. Local administration of the IL-2-secreting plasmacytoma irradiated with a dose of 50 Gy inhibited i.p. plasmacytoma growth more effectively than the administration of non-irradiated, live cell vaccines. Whereas the vaccination with the live cell vaccine could substantially prolong the survival of the tumour-bearing mice but did not significantly induce tumour regressions, the irradiated vaccines could substantially increase the number of tumour-free animals. The irradiated vaccines produce higher amounts of IL-2 than the live cell vaccines both in vitro and in vivo. Depletion of CD4+ and CD8+ effector cells with monoclonal antibodies has significantly decreased the effect of the vaccination. It can be concluded that both, CD4+ and CD8+ T lymphocytes are required for effective IL-2 gene therapy of the X63-Ag8.653 plasmacytoma and that the higher effect of the irradiated vaccines is probably due to their higher IL-2 production.
Símová
J
J
Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Flemingovo nam. 2, 166 37 Prague 6, Czech Republic.
Bubeník
J
J
Jandlová
T
T
Indrová
M
M
D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D019496:Cancer Vaccines; D015316:Genetic Therapy / Q000379:methods; D007376:Interleukin-2 / Q000096:biosynthesis* / Q000235:genetics; D008212:Lymphocyte Depletion; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D010954:Plasmacytoma / Q000276:immunology* / Q000473:pathology / Q000628:therapy*; D014407:Tumor Cells, Cultured / Q000528:radiation effects; D019444:Vaccines, DNA
D019496:Cancer Vaccines; D007376:Interleukin-2; D019444:Vaccines, DNA