The current practice of red blood cell banking for transfusion medicine relies primarily on a six-week liquid storage. A growing demand for red blood cell (RBC) products has prompted the search for alternative preservation methods including dry storage. Being desiccation sensitive, attempts to recover RBCs from the dry state have failed.
This dissertation offers a new mechanistic understanding of desiccation-induced cellular injury that is correlated with the oxidative state of the hemoglobin. The general hypothesis states that RBC desiccation is accompanied with non-physiological oxidation of hemoglobin and, consequently, the release of toxic products capable of compromising cellular recovery through oxidative injury.
Data acquired for this dissertation demonstrates that water loss induces a drastic increase in the rate of hemoglobin oxidation, formation of intracellular reactive oxygen species (ROS), and hemolysis. Pharmacological treatments of the hemoglobins oxygen binding site reveal that hemoglobin-induced cellular injury is more prominent in RBC samples that are partially dehydrated (about 3.5 to 5.5 g H2O/g dry weight) than in samples that are relatively dry ( 2 g H2O/g dry weight). Furthermore, partially dehydrated RBC samples contain higher levels of oxidized lipids than more fully dried samples.
This dissertation also examined the role that glucose and glutathione play in enhancing desiccation tolerance of RBCs. Glucose treatment (5 mmol/L) significantly reduced ROS formation and hemolysis levels in partially dehydrated RBC samples (5.8 0.3 g H2O/g dry weight), but not in samples that are relatively dry (2.8 0.5 g H2O/g dry weight). Treating RBCs with DL-buthionine-(S,R)-sulfoximine, a glutathione depleting agent, was correlated with reduced levels of desiccation-induced hemolysis.
This study suggests that desiccation-induced oxidative injury in RBCs is water dependent corresponding to earlier stages of water loss, in which cells can retain metabolic activity. Pharmacological treatments at this stage can significantly affect cell recovery as demonstrated with modifying the hemoglobins oxygen binding site, glutathione depletion, and glucose supplementation. On the other hand, increased cytoplasmatic viscosity compromises biochemical reactions at lower residual moisture contents, and cellular injury is likely the result of physical and mechanical stress. These differences should be taken into consideration in the design of innovative approaches to RBC preservation.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:AEU.10048/1375 |
| Date | 11 1900 |
| Creators | Kanias, Tamir |
| Contributors | Acker, Jason (Lab Medicine and Pathology) |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Thesis |
| Format | 1251101 bytes, application/pdf |
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