Shikonin Suppresses Human T Lymphocyte Activation through Inhibition of IKKβ Activity and JNK Phosphorylation

Figure 2

Effect of shikonin on inhibition of IL-2 (a and b) and IFN-γ secretion (c and d) in human T lymphocytes stimulated by PMA/ionomycin or OKT-3/CD28. The cells (10⁵/well) were firstly treated with shikonin for 2 h and then stimulated with PMA (20 ng/mL)/ionomycin (1 μM) (P/I) or with the coated OKT-3 (5 μg/mL)/CD28 (1 μg/mL) (OKT-3/CD28) for 48 h. The level of IL-2 and IFN-γ in cell culture supernatants was determined by ELISA method. Data reported represent the mean ± SEM of three independent experiments. Significance of differences shows as *𝑃<0.05, **𝑃<0.01, ***𝑃<0.001.

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