Design and specificity of CSA-functionalized membranes. (A) Schematic representation of the CSA-functionalized supported membrane. Components and the average distance between CSA molecules (<d>) are indicated. In the absence of an energetic favor, the CSA molecules assume a mushroom configuration. (B) Phase contrast images of functionalized membranes with 6-nm CSA spacing intervals reveal specific cytoadhesion of erythrocytes infected with FCR3^CSA (upper left panel), and not of erythrocytes infected with FCR3^Δvar2csa (upper right panel) or uninfected erythrocytes (RBC; lower left panel). FCR3^CSA does not cytoadhere to nonfunctionalized membranes (lower right panel). Cells (4 × 10⁷ mL⁻¹) were allowed to settle on the membranes for 60 minutes under controlled atmospheric conditions before unattached cells were washed out at a wall shear stress of 0.8 Pa. Scale bar, 10 µm. The images were taken using a digital camera (ORCA-ER charge-coupled device camera with Hokawo imaging software; Hamamatsu Photonics) mounted on a light microscope (Axiovert 200; Zeiss), original magnification ×63 (objective LD Achroplan 63x/0.75 corr. Ph2; Zeiss).