Fig. 4.

(A) Fractional surface area loss of HS RBCs after passage through IES. For the band-3–deficient RBCs, the surface area loss is increased with the decreased vertical connectivity. For the spectrin-deficient RBCs, the surface area loss is increased with the decreased spectrin density. The error bars are computed based on pressure gradient values of 5, 8, 10, 15, and 20 Pa$\mathrm{\mu }$m⁻¹. The black dashed line highlights the critical fraction of surface area loss that determines the retention of RBCs reported by ex vivo experiment (5). (B) DI of the band-3–deficient and the spectrin-deficient RBCs at different levels of HS-related protein deficiency. The brown bar graph shows DI of spectrin-deficient RBCs measured by osmotic gradient ektacytometry at a fixed osmolality of 300 mOsmol/kg (30).