Effect of replacing αIIb residues Val298 and Ile374 with different amino acids on the surface expression of αIIbβ3 receptors.

Flow cytometry was performed on 293T cells cotransfected with αIIb constructs containing control, Val298 and Ile374, or substituted (Val298Phe, Val298Leu, Ile374Thr, Ile374Leu, Ile374Val) amino acid residues and a control β3 construct. Cells were incubated with the complex-dependent mAb, 10E5, then with FITC-labeled secondary antibody (shaded) and flow cytometry was performed. Background controls were cells incubated with secondary antibody alone (unshaded). Percentages indicate percent positive of gated cells.