Changes and significance of inflammatory cytokines in sera of mice chronically infected with larvae of Echinococcus granulosus

OBJECTIVE: To investigate the levels of cytokines in the sera of mice chronically infected with the larvae of Echinococcus granulosus, and explore the mechanisms of immune regulation against parasite infection. METHODS: The protoscoleces were isolated from the livers and lungs of sheep infected with E. granulosus, and then inoculated intraperitoneally to BALB/c mice (2 000 for each mouse), to establish the mouse model of E. granulosus infection. The mice in the control group were injected intraperitoneally with an equal volume of PBS. The sera of both control and infected mice were collected to test the levels of multiple cytokines by using the Cytometric Bead Array (CBA) 5 months post-infection. RESULTS: In contrast to the control group, the multiple cysts were found in the abdominal cavity, livers and lungs of the infected mice. Moreover, the levels of inflammatory cytokines such as IL-17A, IL-6, IFN-γ, MCP-1, IL-12P70 and TNF-α in the sera of the infected mice were significantly higher than those in the control group (t = 2.713-9.255, all P < 0.05) while the levels of anti-inflammatory cytokine IL-10 were elevated post-infection (t = 3.936, P < 0.001). CONCLUSIONS: Higher inflammatory cytokines in the mice chronically infected with the larvae of E. granulosus, may benefit for the limitation of parasite growth.