Fig 3.

Inhibition of phagocytosis via integrin αvβ5 knockdown. (A) siRNA-induced inhibition of integrin β5 subunit expression in Stab-2/L cells. The cells were transfected with siRNA or control (con) siRNA with similar GC contents. At 60 h after transfection, the suppression of integrin β5 subunit expression was confirmed by Western blotting. β-Actin (*) of each cell lysate was assessed as a control. (B) Inhibition of aged RBC engulfment by integrin β5 pretreatment. The phagocytic indexes were determined as indicated. The results are expressed as the mean ± SD from at least three experiments. **, P < 0.01 (ANOVA). (C) Stab-2/L cells were preincubated with the indicated amount of monoclonal antibody against stabilin-2 (5G3), β5, or isotype-matched control Ab for 1 h at 37°C before addition of aged RBCs. mIgG, mouse IgG. The phagocytic indexes were determined, and the results are expressed as the mean ± SD from at least three experiments.