T-cell activation by CD3 and CD28 ligation or PMA treatment decreases mFL expression in T lymphocytes.

Cells were cultured with IL-7 (15 ng/mL) for 72 hours under the indicated conditions. Anti(α)-CD3 and CD28 mAbs were present for 72 hours, whereas PMA (20 ng/mL) and metalloproteinase inhibitor BB3103 (1 μM) were added for the last 3 hours of culture only. Expression of mFL was analyzed by FACS. Dotted line indicates staining with isotype-matched control mAb.