Figure 4.

Abnormal RBCs in IEX-1 KO mice. (A) Fast turnover of IEX-1 KO RBCs. WT and KO mice were administered a biotin labeling agent, after which blood samples were obtained at indicated days and incubated with flourescein-labeled avidin and phycoerythrin-conjugated TER119 antibody, followed by flow cytometry to identify biotin+ RBCs. The sample collected 2 h after biotin labeling is arbitrarily set as 100% and a half-life of labeled RBCs is indicated with dashed lines. (B and C) Reduced CD47 expression on RBCs lacking IEX-1. The mean fluorescence intensity (MFI) of CD47 was analyzed with flow cytometry following staining with anti-CD47 and TER-119 antibodies (B). Histogram of CD47 expression was attained on gated TER-119⁺ cells as illustrated in (C). *and **, P<0.05 or 0.01, respectively, in the presence or absence of IEX-1 and n = 6 mice in each group.