Effects of thymopeptide and 4 polysaccharides isolated from Chinese medicine on immune functions of spleen and tumor tissues in U14 cervical cancer-bearing mice

AIM: To identify the enhancement of relatively specific immune responses by thymopeptide and 4 polysaccharides isolated from traditional Chinese medicine in the mice bearing cervical cancer. METHODS: The model of cervical cancer-bearing mice was established by implantation of cervical cancer U14 cells into the armpit of the right forelimb of the mice. Beginning from the 2nd day of tumor implantation, 4 polysaccharides Lycium barbarum polysaccharide (LBP), Angelica sinensis polysaccharide (ASP), Ganodema lucidum polysaccharide (GLP) and Panax ginseng polysaccharide (PGP)], thymopeptide or saline solution were intragastric administered for 21 days according to the experimental design. The animals were then killed, the tumor inhibitory rate and spleen index in treatment groups were compared with those in control group. The splenic T-lymphocytes (TLC) and natural killer (NK) cells, and the content of IFN-γ and IL-10 in the tumor tissues were also determined by flow cytometry and immunohistochemical methods. RESULTS: The order of tumor inhibitory rates was: ASP < PGP < thymopeptide < LBP < GLP. The effects of GLP, LBP and thymopeptide were statistically different from that of control group. No difference of tumor inhibition between PGP/ASP groups and control group was observed. The order of spleen index was: ASP < tumor control group < thymopeptide < GLP < PGP < LBP, that of CD4/CD8 enhancement was: PGP < ASP < GLP < thymopeptide < LBP, and that of CD49b⁺ NK hyperplasia was: ASP < thymopeptide < LBP < GLP < PGP,with statistically significant differences among the groups. The changes of IFN-γ and IL-10 in the tumor tissues showed that Th1/Th2 in thymopeptide group, LBP group and GLP group shifted to Th1. No shift to Th1 in PGP group and ASP group was observed. CONCLUSION: LBP, GLP and thymopeptide show significant inhibitory effects on tumor growth in U14 cervical tumor-bearing mice and can enhance the immune functions in the animals.