Hydrogel Microencapsulation Enhances Cryopreservation of Red Blood Cells with Trehalose

Abstract

Cryopreservation of red blood cells (RBCs) plays a vital role in preserving rare blood and serologic testing, which is essential for clinical transfusion medicine. The main difficulties of the current cryopreservation technique are the high glycerol concentration and the tedious deglycerolization procedure after thawing. In this study, we explored a microencapsulation method for cryopreservation. RBC− hydrogel microcapsules with a diameter of approximately 2.184 ± 0.061 mm were generated by an electrostatic spraying device. Then, 0.7 M trehalose was used as a cryoprotective agent (CPA), and microcapsules were adhered to a stainless steel grid for liquid nitrogen freezing. The results show that compared with the RBCs frozen by cryovials, the recovery of RBCs after microencapsulation is significantly improved, up to a maximum of more than 85%. Additionally, the washing process can be completed using only 0.9% NaCl. After washing, the RBCs maintained their morphology and adenosine 5′-triphosphate (ATP) levels and met clinical transfusion standards. The microencapsulation method provides a promising, referenceable, and more practical strategy for future clinical transfusion medicine.

Investigation into antifreeze performances of natural amino acids for novel CPA development

“…ATP concentration is an important parameter of energy source for the overall functioning of RBCs, which is a significant indicator for RBC metabolism. 52,53 The ATP concentration of RBCs after cryoprotection with 4.5% P + 0.6% F was similar to that of the fresh cells (3.67 vs. 3.96 mM). The result indicated that the RBCs, after cryopreservation with the amino acidbased CPAs, can still maintain their physiological function (Fig.…”

Cryoprotectants for red blood cells: Evaluate safety and effectiveness by in vitro measures

“…One‐step and multistep methods are usually utilized to remove CPAs from cryopreserved cells, whose processes often require cell washing and centrifugation 73–75 . For glycerol‐based freezing methods, intracellular glycerol must be washed by the multi‐step method to avoid posttransfusion intravascular hemolysis 76 . After the deglycerolization process, ~15% of the RBCs are hemolyzed, the RBC morphology alters, and there is ~1% Gly residue in the cells 11,77,78 .…”

Combining Cooling Enhancement and Trehalose Dehydration to Enable Scalable Volume Cryopreservation of Red Blood Cells with Low Concentration of Glycerol

“…[ 49–52 ] Nowadays, to prevent the Leidenfrost effect and improve thermal cooling, simpler tools (e.g., nylon mesh, stainless steel mesh, or medical gauze) were chosen for cryopreservation of a small number of mammalian cells, but they had not yet solved the problem of freezing larger‐volume samples. [ 53–55 ]…”

“…[49][50][51][52] Nowadays, to prevent the Leidenfrost effect and improve thermal cooling, simpler tools (e.g., nylon mesh, stainless steel mesh, or medical gauze) were chosen for cryopreservation of a small number of mammalian cells, but they had not yet solved the problem of freezing larger-volume samples. [53][54][55] In this study, to provide a feasible and straightforward method for scalable volume cryopreservation of human RBCs, we chose a polytetrafluoroethylene (PTFE) tube as the freezing vessel to stably increase the cooling rate. In addition, we continued to use the fine-tuned trehalose dehydration technique to reduce the glycerol requirement from 17.5% to 5%.…”