Reducing Cell-Free Hemoglobin Levels in Freeze-dried Red Blood Cells for Transfusions in Austere Environments.

INTRODUCTION

Current storage methods for red blood cell (RBC) products require refrigeration or freezing, but this can pose significant issues in resource-constrained environments or during national emergencies where there is no access to cold storage equipment. To address this challenge, we are developing a new freeze-dried RBC product that can be stored in a dried state at ambient temperatures for long periods of time. A recently developed freeze-dried RBC product was shown to bind oxygen effectively, but increased hemolysis can occur during the freeze-drying process, which can cause toxicity during transfusion.

MATERIALS AND

METHODS

To mitigate the risk of adverse effects associated with free hemoglobin in transfusions of freeze-dried blood products, this study explores in-line post-processing methods that utilize chelating resin beads to effectively adsorb cell-free hemoglobin. This approach could avoid the limitations of traditional centrifugation-based free hemoglobin removal procedures, which may not be feasible in some settings where freeze-dried RBC products could be utilized.

RESULTS

Non-fluidic and fluidic filtration of RBCs suspended in hemoglobin solutions decreased the amount of cell-free hemoglobin by approximately 80%-90% with no significant decreases in RBC counts. Filtration of freeze-dried and rehydrated RBCs using chelating resin beads as an adsorption matrix reduced free hemoglobin levels by more than 60% compared to freeze-dried and rehydrated RBC solutions without filtration.

CONCLUSIONS

The results demonstrate the efficacy of using chelating resin beads as a post-processing technique to reduce the risk of hemolysis-mediated injury from freeze-dried RBC products. These findings are a key step toward developing effective methods to produce freeze-dried red blood cell products that are safe for transfusion in austere, resource-limited environments.