Figure 5.

Effect of antioxidants on Ca²⁺-induced phosphatidylserine (PS) exposure in RBCs from SCA patients. RBCs were incubated in HK-HBS with bromo-A23187 and different free extracellular [Ca²⁺]s for 30 min in the absence (control) or presence of dithiothreitol (DTT, 0.25 mM, n = 10), N-acetylcysteine (NAC, 10 mM, n = 7) or quercetin (0.1 mM, n = 7). PS was then labeled with FITC-lactadherin and percentage of positive RBCs determined by flow cytometry. PS exposures were normalized to those of control RBCs incubated with a free extracellular [Ca²⁺] of 1 μM. The data for DTT have been previously published (Hannemann et al., 2018). Histograms represent means ± SEM for RBCs from n different patients. **p < 0.01, ***p < 0.001 compared to RBCs in the absence of antioxidant.