HCQ down-regulates TCR-induced CD69 expression.

Jurkat T cells were cultured for 24 hours with varying concentrations of HCQ, then incubated an additional 12 hours in 24-well plates (1 × 10⁶/mL) in medium alone (dotted lines), PMA (50 ng/mL), or anti-TCR mAb C305 (ascites, 1:2000). Cells were then harvested and stained with FITC-conjugated anti-CD69, and fluorescence intensity was measured on a FACScan. Cell counts and viability were indistinguishable in untreated and HCQ-treated cell populations. Representative data from more than 5 similar experiments are shown.