The effect of shark liver oil on the tumor infiltrating lymphocytes and cytokine pattern in mice

Ethnopharmacological relevance: Shark Liver Oil (SLO) is a traditional medicine that has been widely used in Scandinavian folk to augment the immune response in some immune-related diseases, especially as an anti-cancer agent. Aim of the study: The object of this project was to confirm the anti-cancer effect of SLO and the possible involving mechanisms. Materials and methods: Using delayed-type hypersensitivity (DTH) response in normal mice, the optimal dose for stimulation of cellular immunity was obtained and injected intraperitoneally to the tumor-bearing mice. Cytokine pattern of splenic MNCs was tested by ELISA. The percentage of CD4+ and CD8+ lymphocytes in tumor-infiltrating lymphocytes was determined by flow cytometry. Also the rate of increase in tumor volume measured. Results: Our findings indicated that SLO highly augments delayed-type hypersensitivity response against sheep Red Blood Cell (sRBC) in mice. Furthermore, intraperitoneal injection of SLO to tumor-bearing mice could increase T-cell infiltration into the tumor and lower the increasing rate of tumor's Volume. Also, it changes the cytokine pattern of the splenic Mononuclear cells (MNCs) to Th1. Conclusion: Increase in IFN-gamma (resulting in enhanced cellular immunity) and increase in especially CD8+ lymphocytes accompanied by a decrease in tumor size are among the signs of its anti-tumor effect. Accordingly, we suppose that SLO is a good candidate for further studies in cancer therapy. (C) 2009 Published by Elsevier Ireland Ltd.