Immunomodulatory effects of marine oligopeptide preparation from Chum Salmon (Oncorhynchus keta) in mice

Abstract To observe the immunomodulatory effects of marine oligopeptide preparation (MOP) from Chum Salmon ( Oncorhynchus keta ) by the method of enzymatic hydrolysis, female ICR mice (6–8 weeks old) were administered the MOP for four weeks with the dose of 0, 0.22, 0.45 and 1.35 g/kg/body weight. In comparison with the control group, the MOP could significantly enhance the capacity of lymphocyte proliferation induced by the mitogen concanavalin A, the number of plaque-forming cells, natural killer cell activity, the percentage of CD4 + T helper (Th) cells in spleen and the secretion of Th1 (IL-2, IFN-γ) and Th2 (IL-5, IL-6) type cell cytokines. Nevertheless, no significant differences in weight gain, lymphoid organ indices and phagocytosis capacity were observed in our study. These results suggest that MOP is a possible immune stimulant and may strengthen the immune response of its host.