Fig. 3.

Binding of AL-57 IgG to WT LFA-1 activated by agonists as determined by immunofluorescent flow cytometry. K562 transfectants expressing WT LFA-1 and IL-15-cultured human primary T lymphocytes were stained for 20 min at 37°C with 20 μg/ml AL-57, TS2/4, or isotype-matched human or mouse control IgG in Hepes-buffered saline containing 1 mM MgCl₂/1 mM CaCl₂, 5 mM MgCl₂/1 mM EGTA, or 1 mM MnCl₂. Cells were washed and stained with FITC-conjugated goat anti-human or anti-mouse Abs. Staining with AL-57 and TS2/4 is shown as solid lines, and background staining with control IgGs is shown as dashed lines. Numbers within the panels show the specific mean fluorescence intensity of AL-57 and TS2/4.