Study Of Antitumor Activities With Corynebacterium Parvum CPG DNA

Reports about systemic bacterial infection could regress tumor growth have been observed for centuries. Dr. William Coley attempted to explore this effect in the1890s, and performed a series of studies evaluating anti-tumor therapy with bacteria and bacterial products. This resulted in tumor regression but proved to be toxic. In1994Some studies showed that bacterial DNA have played a role in cancer regressing, that does not produce endotoxin. Recently it has been recognized that DNA sequences CpG,which are rich in prokaryotic but not in mammalian DNA,cause the regression of the tumor. Our study is about antitumor immunity of CpG DNA from Corynebacterium parvum(CP-CpG-DNA),and to explore the affect to the immue system and the cytokines.Objective:To study the anti-tumor effects and the immunostimulatory mechanisms of CpG DNA from Corynebacterium parvum.Methods:1. QiAamp DNA Mini Kits were used to extract CpG DNA from Corynebacterium parvum, The absorbance value was measured by SmartSpec Plus at A230nm、A260nm and A280nm, the ratio of A260nm/A280nm was used to determine the CpG DNA purity and the concentration.2. The cytotoxic effects of CP-CpG-DNA on YAC-1cell were determined by MTT.3. Subcutaneous hepatoma was established in mice with Hepal-6cells, the mice were divided into five groups randomLy:normal control group (n=5), model control group (n=5), CP-CpG-DNA group(n=5),CP group(n=5), E.coli CpG DNA group(n=5), were administered every other day for eight times.4. Tumor size and tumor weight were measured. 5. The killing activity of NK cell in tumor-bearing mice were determined by MTT6. IL-12and TNF-α secreted by macrophages in mice were determined using ELISA.7. IL-2levels in serum of micel were determined by ELISA.Results:1. The ratio of A260nm/A280nm was between1.8-2.0. The purity of CP-CpG-DNA was high enough to meet the requirements, the concentration of the CP-CpG-DNA was about105μg/mL.2. The tumor weight of the CP-CpG-DNA group was lighter than the control group, the inhibition rate was about51.3%.3. CP-CpG-DNA could inhibit the activity and the growth of YAC-1cell in vitro, activity and growth inhibition rate increased with the processing of DNA concentration.4. CP-CpG-DNA could enhance the NK cell killing activity of the tumor-bearing mice.5. Macrophages from the tumor-bearing mice secreted the highest levels of IL-12in the CP-CpG-DNA group compared with CP group and E.coli CpG DNA group.6. As compared to the control group, TNF-a levels in CP-CpGDNA-treated mice increased significantly, but little difference was observed among CP-CpG-DNA group, CP group and E.coli CpG DNA group.7. As compared to the control group, IL-2group in CP-CpG-DNA group, CP group and E.coli CpG DNA group increased a little.Conclusion:CP-CpG-DNA can inhibit the growth of the tumor in vitro and in mice experiment. As the immunomodulator, CP-CpG-DNA can play an antitumor effect, CP-CpG-DNA can sigmificently stimulate immune cells activation and proliferation, induce the release of cytokine. CP-CpG-DNA can be used on immunotherapeutic treatment of tumors. rubella virus may have caused serious degree of hurt to pregnant women,and resulted in congenital rubella syndrome to their fetus.At present,a part of the population was infected by RV during pregnancy in our country.To improve the population quality, pregnant especially early pregnant women should detect RV specific IgM antibodies to diagnose whether infect RV or not. Prepared the RV control panel, advanced the accuracy of RV IgM detectiong by ELISA or CLIA.Objective:To establish the control panel for anti-rubella virus IgM antibody detection, which aims to provide a reliable quality control substance for performance evaluation of the RV IgM diagnosis kit based on euzymelinked immunosorbent assay (ELISA) and chemiluminescence(CLIA).Methods:The positive and negative sera were selected by kits, of which five positive serum of different sources were taken as control plate P1-P5,10different sources of negative serum as control plate N1-N10,the L1-L3was produced by the mixture of5positive serum of different sources. Then,the established panel was verified with different kits.Results:The control panel for RV IgM antibody was proved to be successfully established through the verification of the different kits.Conclusion:The quality control panel can be used for the performance evaluation of most RV IgM diagnosis kits which are based on principles of enzyme-linked immunosorbent assay and chemiluminescence,etc.