In vitro and in vivo validation of stored swine erythrocyte viability to establish an experimental model of homologous red blood cell transfusion: a pilot study

Abstract

Objective To develop experimental models of erythrocyte transfusion, the first step is to ensure the viability of the red blood cells transfused. In this pilot study, we assessed the viability of transfused red blood cells with validation in vitro and in vivo of homologous swine erythrocytes stored for 14 days.Methods Blood collected from one Agroceres® swine was stored in two red blood cell units. In vivo validation was performed by labeling the red blood cells with Na251CrO4 and recovering the viable erythrocytes after 24 hours of infusion in one autologous and four homologous animals. In vitro validation was performed at baseline and after 14 days in sixteen red blood cell units by measuring hemoglobin, hematocrit, hemolysis index and free hemoglobin. A post-mortem splenectomy was performed to evaluate the splenic sequestration of erythrocytes, and the radioactivity of the supernatant samples was counted to evaluate intravascular hemolysis.Results After 14 days of storage, the red blood cell units had lower volumes and equivalent total concentrations of hemoglobin and hematocrit compared to human standards. The free hemoglobin concentration increased from 31.0±9.3 to 112.4±31.4mg/dL (p<0.001), and the hemolysis index increased from 0.1±0.1 to 0.5±0.1% (p<0.001). However, these tests were within the acceptable range for human standards. The percentage of radioactivity in supernatant samples was similar at baseline and after 24 hours, thus excluding significant hemolysis. No evidence of splenic sequestration of radioactive erythrocytes was found.Conclusion Swine red blood cells stored for 14 days are viable and can be used in experimental studies of transfusion. These validation experiments are important to aid investigators in establishing experimental models of transfusion.

A novel autotransfusion device saving erythrocytes and platelets used in a 72 h survival swine model of surgically induced controlled blood loss

“…Twelve one year-old female Yucatan mini-pigs were included in the study with a median (min-max) weight of 46.9 (45.75-48.25) kg in the visceral model (n = 5) and 48 (41)(42)(43)(44)(45)(46)(47)(48)(49)(50)(51)(52)(53) kg in the cardiac model (n = 7). Each animal was individually identified by an ear tag (since a few days after birth) to guarantee traceability.…”

“…Coagulation properties of the blood from the collecting reservoir and in the transfusion bag were evaluated by ROTEM assays. EXTEM tests show that the clotting time was considerably increased in the transfusion bag compared to before filtration and washing for both models (for the visceral model, 56 [49][50][51][52][53][54][55][56][57][58][59][60][61][62][63][64][65] s before treatment vs 517 [291-3600] s after the treatment and for the cardiac model, 56.5 [53][54][55][56][57][58][59][60][61] s before the treatment vs 1769 [119-2277] s after). Results expressed as median (min-max) for the visceral (VISC, n = 5) and cardiac models (CARD, n = 4)…”

“…Animals were followed up for 48 hours without any mortality. The porcine model seems to be the most commonly used for blood transfusion studies [48][49][50]. The minipig model (Sus Scrofa domesticus) has been extensively used in hemorrhagic models and cardiovascular research including testing medical devices [51,52].…”

Lessons from sheep models of transfusion

“…Additionally, as the anticoagulants and additive solutions in human blood packs have been optimized for human blood, animal blood products may store differently to human blood products. It is therefore imperative to characterize the similarities and differences between the storage lesions of animal and human blood products when applying homologous transfusion models to the investigation of blood product storage duration effects .…”

“…Comparison of animals commonly used to model transfusion against humans. (Adapted from Simonova et al[19])[2,[13][14][15][16][18][19][20][21][22][23] …”