FIGURE 4:

The frequency of adhesive interactions between an α_IIbβ₃-functionalized AFM tip and cell surfaces increase with exogenous ^RGDP2Y₂R and not ^RGEP2Y₂R. (A) Adhesion frequency of α_IIbβ₃-functionalized AFM cell membranes of P2Y₂R-null WT, ^RGEP2Y₂R, and ^RGDP2Y₂R 1321N1 cells under similar AFM scan conditions. Values are means ± SD of force scans of greater than or equal to five different cell measurements. Statistical significance was determined by Student’s t test ****p < 0.0001. (B–D) Representative single force distance (retraction) curves between α_IIbβ₃-functionalized AFM tip and the surface of parent WT 1321N1 cells devoid of P2Y₂R, and 1321N1 cells expressing exogenous ^RGEP2Y₂R and ^RGDP2Y₂R. The fractions shown represent the number of positive force scans in the numerator and the denominator, the total number of scans for each cell type.