Hinokitiol Negatively Regulates Immune Responses through Cell Cycle Arrest in Concanavalin A-Activated Lymphocytes

Figure 4

Effects of hinokitiol on negative regulators of the cell cycle. (a) Cells were treated with hinokitiol (1–5 μM) in the presence of ConA (10 μg/mL) for 24 h. The specific antibody was used to detect p21. Data are presented as the mean ± SEM (; , , and compared with the ConA (alone)-treated group). (b) Schematic illustration of hinokitiol-mediated inhibition of immune responses in ConA-activated T lymphocytes. Hinokitiol downregulates cyclin D3, Cdk4, and E2F1 expression and upregulates p21 expression and subsequently arrests the cell cycle at the G0/G1 phase. Hinokitiol also attenuates IFN-γ secretion. Finally, hinokitiol negatively regulates immune responses.

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