Fig. 2

Purified CD4⁺ T cells from SLE patients upregulate CD154 after stimulation, while HCQ downregulates CD154. a Purity of the isolated CD4⁺ T cells was 97%. b Purified CD4⁺ T cells from SLE patients (n = 4) and healthy controls (n = 4) were treated with various concentrations of ionomycin for 6 hours (left panel) or 1 μg/ml ionomycin for different time periods (right panel). CD154 expression was measured by flow cytometry. c CD4⁺ T cells were purified from SLE patients and cultured in different concentrations of HCQ (1 × = 600 ng/ml), as indicated, and activated with ionomycin (1 μg/ml) for 6 hours (left panel). Flow cytometry was used to measure CD154 expression (n = 11). ***p < 0.005. Histogram plots of flow cytometry analysis with various concentrations of HCQ are indicated (right panel). HCQ hydroxychloroquine, SLE systemic lupus erythematosus, NEG no HCQ treatment