Maslinic Acid Enhances Immune Responses in Leukemic Mice Through Macrophage Phagocytosis and Natural Killer Cell Activities In Vivo.
BACKGROUND/AIM
Maslinic acid (MA), a pentacyclic triterpene extracted from wax-like coatings of olives, has been shown to reduce cancer cell number through induction of autophagy and apoptosis in many human cancer cells including human leukemia HL-60 cells. In the present study, we investigated whether or not MA affects immune responses in a leukemia mouse model.


MATERIALS AND METHODS
WEHI-3 cells were intraperitonealIy (i.p.) injected into normal BALB/c mice to develop leukemia. Mice were then treated by i.p. injection with MA at different doses (0, 8, 16 and 32 mg/kg) for 2 weeks. After treatment, all animals were weighed and blood, liver and spleen tissues were weighed. Blood or spleen both were used for determination of cell markers or phagocytosis, natural killer (NK) cell activities and T- and B-cell proliferation, respectively, by using a flow cytometric assay.


RESULTS
MA did not significantly affect body, liver, and spleen weights. However, MA increased markers of T-cells (at 16 mg/kg treatment) and monocytes (at 32 mg/kg treatment), but reduced B-cell markers (at 8 mg/kg treatment); MA did not significantly affect cell marker of macrophages. Furthermore, MA increased phagocytosis by macrophages from peripheral blood mononuclear cells and peritoneal cavity at 32 mg/kg treatment and increased NK cell activity at target cell:splenocyte ratio of 25:1 but did not affect B- and T-cell proliferation.


CONCLUSION
MA increased immune responses by enhancing macrophage phagocytosis and NK cell activities in leukemic mice.
['Lai|Kuang-Chi|KC|', 'Peng|Shu-Fen|SF|', 'Liu|Chia-Chi|CC|', 'Huang|Jye-Yu|JY|', 'Kuo|Jung-Yu|JY|', 'Cheng|Zheng-Yu|ZY|', 'Wu|Rick Sai-Chuen|RS|', 'Lin|Chin-Chung|CC|', 'Chen|Jr-Kai|JK|', 'Chung|Jing-Gung|JG|']
D000818:Animals D001402:B-Lymphocytes D003602:Cytotoxicity, Immunologic D004195:Disease Models, Animal D006801:Humans D007694:Killer Cells, Natural D007938:Leukemia D007963:Leukocytes, Mononuclear D008213:Lymphocyte Activation D008264:Macrophages D051379:Mice D010587:Phagocytosis D013154:Spleen D013601:T-Lymphocytes D014315:Triterpenes
Maslinic acid immune responses macrophage natural killer cells leukemia WEHI-3 cells