FIG. 6.

Role of β93Cys in RBC degradation during storage. (A) RBCs were collected from healthy volunteers, (designated fresh) or after 7 or 35 days of storage, and β93Cys levels were measured by BD-NEM labeling. For stored RBCs, BD-NEM labeling to Hb in cell-free fraction and inside RBCs is shown; no cell-free Hb was present in freshly prepared RBCs. Representative Western blot images show signals for β-chain Hb and matched BD-NEM labeling. Shown images are from the same gel (albeit not from adjacent lanes as indicated). Quantitation shows BD-NEM binding normalized to β-chain Hb and mean±SEM (n=3–6). *p<0.0001 by unpaired t-test. NS, not significant by one-way ANOVA. (B) Hemolysis was measured after storage of β93Cys or β93Ala RBC for 1 or 10 days. *p<0.001 by Wilcoxon-matched paired t-test, ^#p<0.03 by the Mann–Whitney t-test. (C) Microparticles were measured after storage of β93Cys or β93Ala RBC for 1 or 10 days. *p<0.05 by paired t-test. No difference in the magnitude of storage-dependent increases in microparticles between either RBC was observed. BD-NEM, BODIPY N-ethylmaleimide. To see this illustration in color, the reader is referred to the web version of this article at www.liebertpub.com/ars