Evaluation of inhibitory effect of tumor vaccine in colon carcinoma model mice / 中国生物制品学杂志

ABSTRACT

Objective@#To evaluate the inhibitory effect of tumor vaccines in colon carcinoma model mice.@*Methods@# Mouse bone marrow⁃derived dendritic cells（BMDCs）were stimulated by using CpG β⁃glucan nanoparticles（CNP）in vitro. The BMDCs were divided into PBS group，NP group（without CpG nanoparticles），Lysate group（MC38 cell lysate）and CpG group（CpG1826），which were determined for the expression of marker molecules on the surface by flow cytometry and for the contents of interleukin⁃6（IL⁃6）and IL⁃12p40 in the culture supernatant by ELISA. The tumor lysate nano⁃vaccine was pre⁃ pared by mixing 50 mg／mL tumor lysate（MC38 cell lysate）with 200 mg／mL CNP in a volume ratio of 1∶1，with which mice were subcutaneously immunized as Vaccine group. Vaccine group，PBS group，CNP group and Lysate group were im⁃ munized once a week，for three times in total. Mice were subcutaneously inoculated with MC38 cells，2 × 105 cells for each， in the right lower limb 1 h after the last immunization，and measured for tumor volume once every three days to plot the tumor growth curve. The ratios of CD3+ CD4+ T and CD3+ CD8+ T cells in the blood were analyzed by flow cytometry and the levels of tumor necrosis factor⁃α（TNF⁃α）and interferon γ（IFNγ）in the blood and spleen of mice were determined by ELISA.@*Results@# CNP effectively increased the expression of CD11c+ CD80+，CD11c+ CD86+，CD11c+ MHC⁃Ⅱ+ and the secretion of IL⁃6 and IL⁃12p40 in BMDCs in vitro，which were significantly higher than those in other 4 groups（t = 4. 3 ~ 46. 2，each P < 0. 05）. Compared with that of the other three groups，the tumor volume of mice in Vaccine group decreased significantly（t =2.6~3.4，eachP <0. 05）；TherewasnosignificantdifferenceinCD3+ CD8+ TandCD3+ CD8+ Tcellratios（t = 0.5~ 1. 9，each P > 0. 05）；The content of IFNγ in blood increased significantly（t = 3. 8 ~ 4. 6，P < 0. 05），while thatof TNF⁃α showed no significant difference（t = 0. 4 ~ 2. 0，each P > 0. 05）；However，the contents of IFN γ and TNF⁃α in spleen increased significantly（t = 6. 3 ~ 13. 0，each P < 0. 001）.@*Conclusion@#The prepared nano⁃vaccine of tumor lysate improvedtheimmune level in mice and effectively inhibited the growth of colon carcinoma.