Abstract: Objective: To investigate the effects of interferonγ (IFNγ) on interleukin10 (IL-10) and mononuclear macrophages in a mouse model of gallbladder cancer.
Methods Mouse models of gallbladder cancer were constructed by inoculating the human gallbladder cancer cell line GBCSD subcutaneously in 20 BALB/C mice, and then all the mice were randomly divided into the IFNγ group and the control group (10 mice in each group). Murine recombinant IFNγ (0.1 mL, 1×105 kU/L, diluted with normal saline) was injected into the tumors in the IFNγ group, and normal saline was injected into the tumors in the control group. The expression of IL10 was detected by ELISA, and the numbers of CD14+ cells (mononuclear macrophages), CD64+ cells (M1 macrophages) and CD206+ cells (M2 macrophages) were counted by the immunohistochemistry. All data were analyzed using the Student′s t test.
Results: The mouse models of gallbladder cancer were successfully constructed 1 week later. Nine mice survived in the IFNγ group, and 7 mice survived in the control group. The tumor weight was (518±138)mg in the IFNγ group and (669±128)mg in the control group, with a significant difference between the 2 groups (t=2.240, P>0.05). The volume of the tumor was (456±172)mm3 in the IFNγ group and (505±146)mm3 in the control group, with no significant difference between the 2 groups (t=1.503, P>0.05). The concentration of IL10 was (58±16)μg/g in the IFNγ group, which was significantly lower than (102±45)μg/g in the control group(t=2.796, P<0.05). The number of mononuclear macrophages was 81±16 in the IFNγ group, which was significantly greater than 50±21 in the control group; the number of M1 macrophages was 66±12 in the IFNγ group, which was significantly greater than 9±4 in the control group; the number of M2 macrophages was 15±4 in the IFNγ group, which was significantly lower than 40±14 in the control group (t=3.214, 13.127, 6.914, P<0.05).
Conclusions: IFNγ could decrease the concentration of IL-10 in the tumor microenvironment, and it could induce the mononuclear macrophage to infiltrate into the stroma of the gallbladder cancer cells, and most of the monocytes and macrophages were differentiate to M1 macrophages.