Table of Contents
ISRN Immunology
Volume 2011 (2011), Article ID 230130, 13 pages
http://dx.doi.org/10.5402/2011/230130
Research Article

Abscopal” Effect of Radiation Therapy Combined with Immune-Therapy Using IFN-γ Gene Transfected Syngeneic Tumor Cells, in Rats with Bilateral Implanted N29 Tumors

1Department of Medical Radiation Physics, Lund University, 221 85 Lund, Sweden
2Rausing Laboratory, Biomedical Centre, Lund University, 221 85 Lund, Sweden
3Department of Neurosurgery, Lund University, 221 85 Lund, Sweden
4Department of Tumor Immunology, Lund University, 221 85 Lund, Sweden

Received 22 June 2011; Accepted 7 August 2011

Academic Editors: A. Clayton, S.-I. Fujii, F. Granucci, and A. Porgador

Copyright © 2011 Bertil R. R. Persson et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

The tumor growth rate response was studied on N29 rat glioma tumor cells subcutaneously implanted on both hind legs of Fischer-344 rats. At around 30 days after inoculation, RT was given with 60Co gamma radiation with 4 daily fractions of 5 Gy only to the right-lateral tumors. At days 26, 42, and 54 after inoculation, immunization was performed with irradiated syngeneic IFNγ-gene transfected cells. Tumor growth rate (TGR % per day) of the right-lateral irradiated tumor was significantly decreased (𝑃<0.01) after RT alone and with the combination of RT and immunization. But immunization alone gave no significant decrease of the TGR but significantly increased time of survival. The TGR of the unirradiated left-lateral tumors was significantly decreased (𝑃<0.02) only in the group of rats treated with RT alone. It is apparent that tumor cells killed by the radiation mediate suppression of tumor cells outside the target area. This effect is called the abscopal effect.