fig2

Figure 2. HCQ inhibits T cell activation in vitro. PBMC from 6 healthy control donors were incubated with 50 µM HCQ for 24 h, then left unstimulated or stimulated with plate-bound anti-CD3 (10 mg/mL UCHT1, Ancell) and anti-CD28 (1 mg/ml, ANC28.1/5D10, Ancell) for 18 h, and analysed by flow cytometry to identify CD3⁺CD4⁺ and CD3⁺CD8⁺ T cell subsets expressing activation markers CD69 and CD25. Statistical significance was assessed by the Mann-Whitney test. **P < 0.01.