With over 10.5 million units of red blood cells (RBCs) transfused in 2021 in the United States alone, blood transfusions are one of the most common hospital procedures. These life-saving interventions are necessary to treat a variety of conditions that result in decreased hemoglobin levels. Common causes include anemia, hemoglobinopathy, cancer, chemotherapy, radiotherapy, and blood loss from trauma or major surgeries.Despite centuries of research into the storage of RBCs for transfusion, current methods cannot prevent degradation of these cells. Detrimental biochemical and physical changes occur after even short periods of storage. This collection of harmful storage-induced changes is known as the storage lesion. The storage lesion can be broadly categorized into oxidative damages and metabolic impairments. Oxidative damages include generation of reactive oxygen species, lipid and protein oxidation, and degradation of cellular structure leading to severe morphological changes. Metabolic impairments lead to accumulation of lactate, acidifying the cellular milieu, and decreases in adenosine triphosphate (ATP) and 2,3-diphosphoglycerate levels. Transfusion of RBCs significantly impacted by the storage lesion raises questions of patient safety. Though contemporary transfusion medicine has mitigated clinical complications from these procedures, they are not without risk. Complications range from transfusion-transmitted infections to fatal acute reactions, such as transfusion-associated circulatory overload. Minimizing the number of transfusions required is a key objective in blood banking research. This may be achieved by improving the efficacy of transfusions through reduction of the storage lesion. Here, this is addressed through the use of modified additive solutions, which are used to prolong viability of RBCs in storage, and investigation of post-storage cellular rejuvenation. The additive solutions used today contain extreme amounts of glucose, ranging from 45 mmol L−1 to 111 mmol L−1. Such hyperglycemic conditions have been implicated in the development of various aspects of the storage lesion. Previous reports have demonstrated that a normoglycemic additive solution containing just 5.5 mmol L−1 glucose is effective in reducing oxidative stress and osmotic fragility in stored RBCs as well as increasing ATP release and cellular deformability. As glucose is metabolized throughout storage, an RBC feeding system was previously developed to automate maintenance of normoglycemic conditions. However, aspects of the design of this system limited experimental control and regulatory compliance, and therefore translational potential. Here, a second-generation RBC feeding system is developed and employed in additional normoglycemic RBC storage studies. Beyond validating the performance of this system, benefits of normoglycemic storage such as reduced cellular glycation and hemolysis are confirmed. Expanding on previous reports, rejuvenation of RBCs stored under these conditions via post-storage washing is investigated. This rejuvenation results in significant improvements to the health of stored RBCs. Both cellular deformability and morphology were consistently restored to near-normal. Next, the rejuvenation potential of C-peptide, a pancreatic hormone, is reviewed. There is a significant overlap between certain aspects of the storage lesion and the dysfunction of RBCs from people with type 1 diabetes (T1D). This includes reduced cellular deformability and ATP release, increased glycation and oxidative stress, and morphological changes. Consistent exposure to hyperglycemic environments may be responsible for these mutual impairments. Extensive study has shown this proinsulin-derived peptide to interact with RBCs, eliciting beneficial effects. Reports include improvements to cellular deformability, glucose metabolism, and ATP release, including enhanced RBC function in vivo. Thus, C-peptide may be an excellent candidate not just as an auxiliary therapeutic for T1D, but as a rejuvenating agent for RBC storage as well. A comprehensive review of the applications of a functional C-peptide formulation is provided. Preclinical development of this product is initiated, including studies into the efficacy of the proposed formulation. Inconsistencies in C-peptide function then lead to a thorough investigation to identify key developmental roadblocks. A resolution is offered, and a path toward successful in vivo clinical studies is laid out.
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