Down-regulation of IL-2R expression by Lptn.

CD4⁺ T cells were activated for 3 days with the indicated stimuli, then stained with the FITC- or PE-conjugated mAbs listed in “Materials and methods,” including IL-2Rα mAb, and analyzed by FACS. Mean fluorescence intensity (MFI) and percent of positive cells relative to IL-2Rα expression are indicated. For unstimulated cells, these values were 11% and 6%. For IL-2Rβ, expression of which is not affected by Lptn, they were 8% and 4% (medium), 17% and 61% (CD3), 16% and 50% (CD3+Lptn), 22% and 71% (CD3+Lptn+anti-Lptn), 20% and 64% (CD3+RANTES), 17% and 55% (CD3+RANTES+anti-RANTES). This experiment is 1 among 3 independent determinations performed with different donors.