Exploring the molecular mechanism of dihydroartemisinin regulating spleen immunity based on proteomics and phosphoproteomic

The molecular mechanisms through which dihydroartemisinin (DHA) induces immunomodulation in vivo remain unclear. Herein, DHA-regulated proteins and their phosphorylation profiles were identified and characterized, in the spleens of mice, using proteomics and phosphoproteomic approaches. We found that DHA upregulates proliferation-associated protein (cyclin-dependent kinases, Ki67, and mini-chromosome maintenance and proliferating cell nuclear antigen) expression via modulation of mitogen-activated protein kinase (MAPK) - activator protein 1 (AP-1) signaling pathway activity. In addition, DHA promoted the proliferation of CD4 T naïve, proliferated CD25+CD4+ T-cells, and BrdU+ interferon (IFN)-γ-producing CD8+ T cells. These predicted mechanisms of action were then validated in a Plasmodium berghei ANKA-infected mouse model of malaria and a cyclophosphamide-induced immunosuppression model. Collectively, the findings of this study, for the first time, provide robust evidence that DHA induced the expansion of the splenic T-cell pool through MAPK-AP1 signaling. The data provided in-depth knowledge in the mechanism of DHA-mediated immunomodulation.