title: Post-transfusion survival of biotin-labeled allogeneic RBCs in adult horses.
abstract: BACKGROUND
  Post-transfusion survival of allogeneic RBCs has been reported to be much shorter in horses than in other species. We hypothesized that post-transfusion survival of biotinylated allogeneic equine RBCs would be greater than the survival previously reported from studies using radioactive RBC-labeling techniques.
  
  
  OBJECTIVE
  The study objective was to determine post-transfusion survival of N-hydroxysuccinimide (NHS)-biotin-labeled allogeneic equine RBCs transfused into adult horses.
  
  
  METHODS
  Horses were adults and included 5 donors and 5 recipients. All horses were blood-typed, and donors were paired with recipients based upon blood type and crossmatch results. Donor blood was collected in a volume of 4 L into citrate phosphate dextrose adenine-1 and stored for 24 hours, labeled with NHS-biotin, and re-infused into recipients. Post-transfusion blood samples were collected at 15 minutes and at 1, 2, 3, 5, 7, 14, 21, 28, and 35 days. Biotin-labeled RBCs were detected by flow cytometry using streptavidin-phycoerythrin. Post-transfusion survival at 24 hours, lifespan, and half-life of biotinylated RBCs were determined.
  
  
  RESULTS
  Mean ± SD survival of biotinylated RBCs at 24 hours post-transfusion was 95 ± 24%; the mean lifespan of transfused allogeneic RBCs was 39 days based on calculation of a linear regression survival curve, and mean post-transfusion RBC half-life was 20 days.
  
  
  CONCLUSIONS
  Post-transfusion survival of 24-hour stored equine allogeneic RBCs was greater than previously reported but less than that observed for other companion animal species. Mechanisms for the relatively short post-transfusion lifespan of allogeneic equine RBCs remain unknown and warrant further study.
authors.affiliation: Department of Veterinary Clinical Sciences, College of Veterinary Medicine, The Ohio State University, Columbus, OH, USA.
authors.forename: Margaret C
authors.initials: MC
authors.lastname: Mudge
authors.forename: Naomi J
authors.initials: NJ
authors.lastname: Walker
authors.forename: Dori L
authors.initials: DL
authors.lastname: Borjesson
authors.forename: Fred
authors.initials: F
authors.lastname: Librach
authors.forename: Jennifer L
authors.initials: JL
authors.lastname: Johns
authors.forename: Sean D
authors.initials: SD
authors.lastname: Owens
mesh_terms: D000818:Animals; D019921:Biotinylation / Q000379:methods / Q000662:veterinary; D001788:Blood Grouping and Crossmatching / Q000662:veterinary; D002470:Cell Survival / Q000502:physiology; D017707:Erythrocyte Transfusion / Q000662:veterinary*; D004912:Erythrocytes / Q000502:physiology*; D005260:Female; D006207:Half-Life; D006736:Horses / Q000097:blood*; D016014:Linear Models; D008297:Male; D013045:Species Specificity; D013194:Staining and Labeling; D013997:Time Factors; D014184:Transplantation, Homologous / Q000662:veterinary