Adhesion of α_Mβ₂- and mock-transfected cells to Glu-Pg. α_Mβ₂-expressing (•) and mock-transfected (▴) HEK 293 cells (5 × 10⁴) labeled with calcein-AM in HBSS/HEPES were added to wells coated with different concentrations of Glu-Pg and postcoated with 0.5% PVP. Some α_Mβ₂-expressing (○) and mock-transfected (▵) cells were preincubated with mAb 44a (40 μg/mL). Glu-Pg was pretreated with 2 mM PMSF for 15 minutes at 22°C to prevent its activation on the surface. After 25 minutes at 37°C, nonadherent cells were removed by 3 washes with PBS. Fluorescence of adherent cells was measured in a fluorescent plate reader and converted to cell numbers. A representative of 3 independent experiments is shown. Data shown are means of triplicate determinations, and error bars represent SE.