Normal in vivo survival of CD59a-deficient and CD59a/DAF–double-deficient but not Crry-deficient mouse erythrocytes.
(A) Erythrocyte counts (× 1012/L) and blood hemoglobin concentrations (g/dL) were not significantly different between wild-type (i, n = 5 mice), CD59a knockout (ii, n = 5 mice), and CD59a/DAF double-knockout mice (iii, n = 5 mice). (B) Biotinylated erythrocytes could be easily distinguished from unlabeled cells by FACS analysis (example shown is erythrocytes taken from a C57BL/6 mouse that received biotinylated wild-type erythrocytes 12 hours earlier). (C) Percentage of biotinylated erythrocytes remaining at day 3 and 5 after reinfusion. There was no significant difference between wild-type and CD59a knockout or CD59a/DAF double-knockout mice. Experiment 1: cells were taken from wild-type (i, n = 3 mice); CD59a knockout (ii, n = 4 mice), or CD59a/DAF double-knockout mice (iii, n = 4 mice) and, after labeling, were reinfused into the same donor mice. Experiment 2: cells were taken from wild-type (i, n = 3 mice), CD59a knockout (ii, n = 3 mice), or CD59a/DAF double-knockout mice (iii, n = 3 mice) and, after labeling, were transfused into male C57BL/6 mice. Percentage of labeled cells detected in Experiment 1 at days 3 and 5 were generally lower. This may reflect increased hematopoiesis stimulated by the initial blood drawing. (D) Erythrocytes from Crry-deficient mice (filled circles, obtained from Crry/C3 double-knockout mice) but not from Crry-sufficient littermate controls (Crry wild-type but C3-deficient, filled triangles) were rapidly eliminated after transfusion into wild-type recipients. In contrast, Crry-deficient erythrocytes (obtained from Crry/C3 double-knockout mice) were stable when transfused into C3 knockout recipient mice (open circles). Average values from 2 mice in each group are shown. The difference between the open circle and filled triangle curves is not considered significant as typically between 80% and 100% of labeled cells remain when cells are assayed at day 3. In panels C and D, blood samples were taken at 5 minutes after labeled cells were intravenously infused, and the percentage of labeled cells at this time point was regarded as 100% for later reference. Data shown are representative of at least 3 different experiments.
