Treatment Of Rat Glioma With Vaccine Which Consists Of Allogeneic Glioma Cells And Their Lysates With Syngenic Glioma Cell Lysates

objective: This study investigated the therapeutic effect of the vaccine which consists of allogeneic C6 glioma cells and their lysates with syngenic 9L glioma cell lysates,and the changes of invasiveness after the vaccine treatment,so as to provide more feasible solutions for glioma immunotherapy.Methods :(1)Adopting the stereotactic technique,1x106/10?l 9L glioma cell suspension was injected into the right caudate nucleus of Fisher 344 rats to establish 9L/ Fisher 344 rat glioma orthotopic model.(2)After inoculation,the rats were randomly divided into three groups:control group,the 200000-units treatment group,and the 300000-units treatment group,10 rats in each group.Control group receives no treatment;the200000-units treatment group receives subcutaneous injection of C6 cells(200,000)plus C6 cells lysate(200,000 cells)plus 9L syngeneic lysate(200,000cells),while the 300000-units treatment group receives subcutaneous injection of C6 cells(300,000)plus C6 cells lysate(300,000 cells)plus 9L syngeneic lysate(300,000 cells).All treatments were given on the first day after intracranial inoculation of 9L cells.(3)The rats survival conditions and survival time were observed andrecorded within 50 days after injecting 9L cells into the brain.The glioma volume was dynamic monitored with MRI scanner at the 10 th,20th,30 th,40th and 50 th day after inoculation of 9L cells.To observe the changes of histopathology and invasiveness of rat glioma,the brains of rats were isolated on the 20 th day after implanting of 9L cells(n = 1,for each group)for HE staining and immunohistochemical staining of Podoplanin and Fascin.Results:(1)Within the next 50 days after inoculation of 9L cells,the survival rate of control group was 0;the survival rate of 200000-units treatment group was 89%;the survival rate of the 300000-units treatment group was100%.The survival time of the treatment group was significantly longer than that of the control group,and the difference was statistically significant(P <0.05).There was no significant difference between the 200000-units treatment group and the 300000-units treatment group(P>0.05)(2)All rats with enhanced MRI examination showed the right caudate nucleus was significantly enhanced,and the success rate of the experimental model was 100%.MRI dynamic observation showed that with the increase of tumor age,the glioma of control group continued to grow,while the treatment group grew at first but then decreased;The glioma volume were calculated at20 th day after 9L cells were inoculated,the glioma volume of control group was 451.25 ± 9.36 mm3,the glioma volume of 200000-units treatment group was 122.5 ± 22.30 mm3,the glioma volume of 300000-units treatment group was 112.06 ± 17.97 mm3;The single factor variance analysis showed that theglioma volume of control group was significantly greater than the treatment group,the difference was statistically significant(P<0.05);there was no significant difference between the 200000-units treatment group and the300000-units treatment group(P>0.05)(3)HE staining showed that in the control group,the density of glioma cells was high,and the glioma cells were closely arranged like a nest,along with hemorrhage,necrosis and neovascularization in some areas;while in the treatment group,the cell density was low,the typical nest arrangement and neovascularization are scarce.Immunohistochemistry showed that the expression of Podoplanin and Fascin in the control group was strongly positive,while in the treatment group,the expression of Podoplanin and Fascin were decreased,and the decrease of Podoplanin staining was more significant than that of Fascin;Podoplanin and Fascin can be observed in a small number of glioma cells in the 200000-units treatment group and the 300000-units treatment group,but there was no significant difference between the two groups.Conclusion: This study successfully established 9L/ Fisher 344 rat glioma model,and gave treatment for the vaccine which consists of allogeneic C6 glioma cells and their lysates with syngenic 9L glioma cell lysates in 1th days after inoculation.The experimental results showed that the vaccine can break the immune tolerance to tumor of tumor-bearing body,induce antitumor immune response of tumor-bearing mice,prevent immune escape,prolong thesurvival time of tumor-bearing rats and reduce the invasiveness of glioma.