Evaluation of cell proliferation and interleukine-4 and interferon γ level measurement in Balb/c mice with experimental fibrosarcoma tumor by combination of Gp96-tumor peptide and naloxon

(Received 22 Aug, 2008; Accepted 24 Sep, 2008) Abstract Background and purpose: In spite of the increasing progress in tumor treatment by current methods like surgery, chemotherapy and etc, medical sciences are unable to treat tumors. In this respect, immunology has opened a new window for tumor treatment; nowadays tumor immunotherapy is an accepted strategy for treatment of some tumors at least in some animal models. The goal of this study is the evaluation of immunotherapy using gp96- tumor peptide complex and its combination with naloxon as an opioid receptor antagonist to achieve of cellular immunity against tumorsMaterials and methods: In this study firstly, gp96 – tumor peptide complexes were purified from WEHI164 cells line using srivastava method. In the next stage, the mice, made tumoric befor by the injection of tumor cells, then were divided in to four groups. Control group were injected by PBS, test group1 were injected by naloxon, test group2 were injected by gp96 – tumor peptide complex and test group3 were injected by combination of naloxon and gp96 – tumor peptide complex. To evaluation the efficacy of vaccination, after several days, tumor volume was recorded; then the mice were killed and the spleanic cells were extracted in sterile condition. MTT test was done for cells proliferation study. Supernatant of cultured cells were collected and assayed by ELISA kits for measuring IL-4 and IFN-γ.Results: Result of protein purification had showen , purified gp96 Isoform has Molecular Weight of 66 kilo dalton.Results of tumor volume had shown that, there is no significant difference between test and control groups. Results of MTT test had shown that, there is no significant difference between test and control groups. IL-4 assay study had showed that, there is no significant difference between test group1, group2 and control group but test group3 has significantly decreased in IL-4 amount when compared with control group. Results of IFN-γ assay showed that, there is no significant difference between test group1 and control group, but test group2 and group3 has significantly increased in IFN-γ amount when compared with control group.Conclusion: It can be concluded from this study is that, prophylactic immunotherapy of tumor by combination of gp96-tumor peptide complex and naloxon, can increase IFN-γ, and, probably in a higher dosage, it may stimulate immune system more to become more potent to even decrease tumor volume. J Mazand Univ Med Sci 2008; 18(66): 1-9 (Persian