Sickle red blood cells exposed to lower sodium fluids are less adherent to human endothelium under postcapillary venular shear stress. (A) Macroscopic (left) and microscopic (right) images of the 4-chamber microfluidic device, whereby 4 lanes with separate inlets and outlets are each 46 µm tall, 100 µm wide, and 4 mm in length along the uncurving portion of the device. (B) Brightfield (left) and fluorescence (right, membrane dye) microscopy images of the microfluidic device endothelialized to confluence. (C) Fluorescence images of stained sRBCs adhered to human umbilical vein endothelial cells. sRBCs exposed to fluids with higher sodium levels adhere to endothelium under a postcapillary venular shear stress of 1 dyne/cm2. (Boxed number corresponds to number of sRBCs adherent to endothelium in that region of interest.) (D) In total, sRBCs were isolated from 6 patients. sRBCs were less adherent when exposed to the most hypotonic admixtures. Bars and lines represent mean ± standard deviation from 3 patients for each experimental condition, except the most hypotonic (N = 2).
