Plasmodium yoelii infection inhibits murine leukaemia WEHI-3 cell proliferation in vivo by promoting immune responses

Abstract

BackgroundLeukaemia is a malignant leukocyte disorder with a high fatality rate, and current treatments for this disease are unsatisfactory. Therefore, new therapeutic strategies for leukaemia must be developed. Malaria parasite infection has been shown to be effective at combating certain neoplasms in animal experiments. This study is to demonstrate the anti-leukaemia activity of malaria parasite Plasmodium yoelii (P. yoelii) infection,.MethodsIn this study, the proportion of CD3, CD19, CD11b and Mac-3 cells was analysed by flow cytometry; the levels of IFN-γ and TNF-α in individual serum samples were measured by enzyme-linked immunosorbent assay, and the phagocytic activity of macrophages and natural killer (NK) cell activity were measured by flow cytometry.ResultsWe found that P. yoelii infection significantly attenuated the growth of WEHI-3 cells in mice. In addition, tumor cell infiltration into the murine liver and spleen was markedly reduced. We also demonstrated that malaria parasite infection elicited anti-leukaemia activity by promoting immune responses, including increasing the surface markers of T cells (CD3) and B cells (CD19); decreasing the surface markers of monocytes (CD11b) and macrophages (Mac-3); inducing the secretion of IFN-γ and TNF-α; and increasing NK cell and macrophage activity.ConclusionsMalaria parasite infection significantly decreases the number of myeloblasts and inhibits neoplasm proliferation in mice. In addition, malaria parasite infection inhibits murine leukaemia by promoting immune responses.Electronic supplementary materialThe online version of this article (10.1186/s40249-018-0433-4) contains supplementary material, which is available to authorized users.

Plasmodium infection suppresses colon cancer growth by inhibiting proliferation and promoting apoptosis associated with disrupting mitochondrial biogenesis and mitophagy in mice

“…Because of the high incidence and mortality associated with colon cancer, researchers devoted to reducing mortality and improving patients' quality of life are continuously seeking new treatments to inhibit the growth, recurrence, and metastasis of colon cancer [ 34 ]. The murine model is a common model for cancer research [ 35 ], and the P. yoelii 17XNL nonlethal strain of malaria parasite can be used to infect the mice for examining its antitumor effect without causing the death of the animals [ 5 – 7 ]. Previously, our team and other researchers have all found that Plasmodium infection had antitumor effects on some cancers in different mouse models, but it was not clear whether it would have similar influences on colon cancer.…”

“…According to a report, a negative correlation was found between the incidence of malaria and the mortality rate of some cancers globally from 1955 to 2008 [ 4 ]. The antitumor effect of Plasmodium infection has been reported in animal studies, including lung cancer [ 5 ], hepatocellular carcinoma [ 6 ], leukemia [ 7 ], and melanoma [ 8 ]. However, it has not been reported whether Plasmodium infection can inhibit colon cancer.…”