Effects of Antioxidative, DPPH Radical Scavenging Activity and Antithrombogenic by the Extract of Sancho ( Zanthoxylum Schinifolium)

Effects of root, stem and leaf extract of sancho (Zanthoxylum schinifolium) on the inhibition of lipid peroxidation in the hepatic microsome of rat, DPPH radical scavenging activity and activated partial thromboplastin times (APTT) were examined in vitro. The highest inhibition of hepatic microsomal lipid peroxidation was observed by ethyl acetate fraction than that of methylene chloride fraction of the root and stem extracts. The high inhibition of lipid peroxidation was determined in the leaf, the root and the stem in order. The DPPH radical scavenging activity of ethyl acetate fraction was higher than that of n-butanol fraction and it was similar to the root and the steam extract. It was similar to the inhibition of hepatic microsomal lipid peroxidation. The DPPH radical scavenging activity was the highest in 2.500 mg/mL of ethyl acetate fraction and it was 4.4 fold higher than that of h-tocopherol, as an antioxidant standard. The DPPH radical scavenging activity was dependent on the extract concentration in the range of 0.125 - 5.000 mg/mL. The thromboplastin times were higher than that of n-butanol fraction and it was similar to the root and the steam extracts. The leaf extract showed the highest antithrombogenic effect followed by the stem and then the root extract. The activated partial thromboplastin times were dependent on the extract concentration in the range of 0.100 - 2.000 mg/mL. Consequently, the effects of antioxidative, DPPH radical scavenging activity and antithrombogenic of Z. schinifolium was observed due to the inhibition of lipid peroxidation and the DPPH radical scavenging activity by methylene chloride, n-butanol and ethyl acetate fraction of the leaf extract.

Application of Apoptogenic Pretreatment to Enhance Anti-tumor Immunity of Granulocyte-Macrophage Colony Stimulating Factor (GM-CSF)-secreting CT26 Tumor Cells

BACKGROUND: As an attempt to develop a strategy to improve the protective immune response to GM-CSF-secreting CT26 (GM-CSF/CT26) tumor vaccine, we have investigated whether the apoptogenic treatment of GM-CSF/CT26 prior to vaccination enhances the induction of anti-tumor immune response in mouse model. METHODS: A carcinogen- induced mouse colorectal tumor, CT26 was transfected with GM-CSF gene using a retroviral vector to generate GM-CSF-secreting CT26 (CT26/GM-CSF). The CT26/GM-CSF was treated with gamma-irradiation or mitomycin C to induce apoptosis and vaccinated into BALB/c mice. After 7 days, the mice were injected with a lethal dose of challenge live CT26 cells to examine the protective effect of tumor vaccination in vivo. RESULTS: Although both apoptotic and necrotic CT26/GM-CSF vaccines were able to enhance anti-tumor immune response, apoptotic CT26/GM-CSF induced by pretreatment with gamma-irradiation (50,000 rads) was the most potent in generating the anti-tumor immunity, and thus 100% of mice vaccinated with the apoptotic cells remained tumor free for more than 60 days after tumor challenge. CONCLUSION: Apoptogenic pretreatment of GM-CSF-secreting CT26 tumor vaccine by gamma-irradiation (50,000 rads) resulted in a significant enhancement in inducing the protective anti-tumor immunity. A rapid induction of apoptosis of CT26/GM-CSF tumor vaccine at the vaccine site might be critical for the enhancement in anti-tumor immune response to tumor vaccine.

Generation of Renal Cell Carcinoma-specific CD4+ /CD8+ T Cells Restricted by an HLA-39 from a RCC Patient Vaccinated with GM-CSF Gene-Transduced Tumor Cells

BACKGROUND: Granulocyte-macrophage colony-stimulating factor (GM-CSF) gene- transduced tumor cell vaccines induce very potent systemic anti-tumor immunity in preclinical and clinical models. Our previous phase I clinical trial in patients with metastatic renal cell carcinoma (RCC) has demonstrated both immune cell infiltration at vaccine sites and T cell-mediated delayed-type hypersensitivity (DTH) response to whole tumor cell vaccines. METHODS: To investigate the immune responses to autologous genetically- modified tumor cell vaccines, tumor-specific CD8+ T cell lines were generated from peripheral blood lymphocytes (PBL) of a RCC patient 1.24 by repeated in vitro stimulation with either B7.1-transduced autologous RCC tumor cells or B7.1-transduced autologous tumor cells treated with interferon gamma (IFNgamma), and cloned by limiting dilution. RESULTS: Among several RCC-specific cytotoxic T lymphocytes (CTLs), a CD4+ /CD8+ double positive T cell clone (17/A2) appeared to recognize IFNgamma-treated autologous RCC restricted by HLA-B39. The 17/A2 also recognized other HLA-B39 positive RCC tumor cells after IFNgamma treatment. CONCLUSION: These results demonstrate that autologous RCC vaccination successfully generates the tumor-specific CTL 17/A2, and suggest that the presentation and recognition of the tumor antigen by the 17/A2 might be upregulated by IFNgamma.