title: 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±31.4 mg/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.
  
  
  CONCLUSIONS
  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.
authors.affiliation: Instituto de Ensino e Pesquisa, Hospital Sírio-Libanês, São Paulo, SP, Brasil.
authors.forename: Silvana
authors.initials: S
authors.lastname: Biagini
authors.affiliation: Departamento de Medicina Nuclear, Hospital Sírio-Libanês, São Paulo, SP, Brasil.
authors.forename: Paulo Aguirre
authors.initials: PA
authors.lastname: Costa
authors.affiliation: Instituto de Ensino e Pesquisa, Hospital Sírio-Libanês, São Paulo, SP, Brasil.
authors.forename: Silvano
authors.initials: S
authors.lastname: Wendel
authors.affiliation: Instituto de Ensino e Pesquisa, Hospital Sírio-Libanês, São Paulo, SP, Brasil.
authors.forename: Guilherme
authors.initials: G
authors.lastname: Schettino
authors.affiliation: Instituto de Ensino e Pesquisa, Hospital Sírio-Libanês, São Paulo, SP, Brasil.
authors.forename: Luciano Cesar Pontes
authors.initials: LC
authors.lastname: Azevedo
mesh_terms: D000818:Animals; D001793:Blood Preservation / Q000379:methods; D002470:Cell Survival / Q000502:physiology; D017707:Erythrocyte Transfusion / Q000379:methods*; D004912:Erythrocytes / Q000166:cytology*; D006400:Hematocrit; D006454:Hemoglobins / Q000378:metabolism; D006461:Hemolysis / Q000502:physiology; D006801:Humans; D008297:Male; D023421:Models, Animal; D010865:Pilot Projects; D013045:Species Specificity; D013154:Spleen / Q000166:cytology; D013552:Swine; D013997:Time Factors
chemical_list: D006454:Hemoglobins