ABSTRACT
Objective: To investigate the antitumor effect of lactobacillus peptidoglycan (PG) and explore its possible mechanisms. Methods: The inhibition for colon tumor growth, and the influence on the activities of CTL, NK, PM?, IL-1, IL-2, TNF-?, IFN-?and nitric oxide secretion were investigated in mice by cell culture, DNA agrose gel electrophoresis, respectively. Results: Growth in vivo of CT26 colon tumor was significantly inhibited by ip injection of PG. PG also induced significantly the activities of IL-1, TNF-?, IFN-?, CTL, NK, PM?and the production of nitric oxide, but had no effect on the activity of IL-2. Conclusion: The peptidoglycan derived from lactobacillus inhibited the colon tumor growth through activation of murine immunity. The antitumor effect of PG maybe partly if not all, induced, by the enhanced production of IFN-?, TNF-?and NO, through activation of NK cell and PM?. Key word: peptidoglycan; antitumor; immunity; cell activity; cytokine