Vox, PKR activator, and GBT021601 reduce Band 3 tyrosine phosphorylation in HbSS RBCs under normoxia and hypoxia. (A) A total of 20 μg of total protein was loaded per lane for all immunoblots. Representative anti–Band 3 immunoblots for untreated and treated HbAA and HbSS RBCs (Vox, PKR activator, GBT021601). (B) Band 3 tyrosine phosphorylation levels in HbAA RBCs were unaffected by treatment with Vox or PKR activator (HbAA vs HbAA + Vox and HbAA + PKR; n = 7; ns, P > .05; Wilcoxon test). (C) Under normoxia, Band 3 tyrosine phosphorylation levels were significantly reduced in HbSS RBCs treated with Vox (HbSS vs HbSS + Vox; n = 22; ∗∗∗P < .001; t test), PKR activator (HbSS vs HbSS + PKR; n = 22; ∗∗∗P < .001; t test), and GBT021601 (HbSS vs HbSS + GBT021601; n = 5; ∗P < .05; t test). (D) Similar reductions were observed under hypoxia (HbSS + Vox [n = 10; ∗∗P < .01]; HbSS + PKR [n = 10; ∗∗P < .01]; HbSS + GBT021601 [n = 10; ∗∗P < .01; t test]). Error bars are presented as mean ± SEM.