Effects of Oxidative Damage on In Vivo Aging, Density, and Survival of Baboon Red Blood Cells

摘要

To assess the relationships among density, age, and survival of baboon red blood cells, hydrogen peroxide-treated (oxidized) red blood cells and untreated (non-oxidized) red blood cells were labeled with Cr-51 and autotransfused. Hydrogen peroxide in a final concentration of 339 micro-mol/liter was used to treat the baboon red blood cells. Blood samples were collected following autotransfusion of the non-oxidized and oxidized red blood cells. These samples were processed as unfractionated red blood cells and as fractionated top, intermediate, and bottom red blood cells consisting of 6 bands isolated using percoll-hypaque density gradients. Oxidized unfractionated red blood cells and oxidized red blood cells in the bottom fraction consisting of 6 bands exhibited significantly reduced Cr-51 24-hour posttransfusion survival values. The T-1/2 values in the bottom fraction were significantly lower in the oxidized than in the non-oxidized red blood cells. As the more dense red blood cells were removed from the circulation, the movement of radioactivity from the less dense top red blood cell fraction to the more dense bottom fraction was reduced. In another aspect of this study, non-oxidized and oxidized unfractionated and fractionated red blood cells were labeled with biotin. Percoll hypaque density gradients were used to separate the bottom red blood cell fraction containing 3 bands or 6 bands. Twenty minutes after the autotransfusion of these biotin-labeled non-fractionated and fractionated red blood cells, blood samples were collected. The biotin-labeled red blood cells were recovered on avidin plates, labeled with Cr-51, and autotransfused. Samples were collected for 24-hour posttransfusion survival and lifespan measurement. The 24-hour posttransfusion survival values of the oxidized non-fractionated red blood cells were only 77% compared to 89% for the non-oxidized non-fractionated red blood cells.