title: A novel model for studies of blood-mediated long-term responses to cellular transplants.
abstract: OBJECTIVE
  Interaction between blood and bio-surfaces is important in many medical fields. With the aim of studying blood-mediated reactions to cellular transplants, we developed a whole-blood model for incubation of small volumes for up to 48 h.
  
  
  METHODS
  Heparinized polyvinyl chloride tubing was cut in suitable lengths and sealed to create small bags. Multiple bags, with fresh venous blood, were incubated attached to a rotating wheel at 37°C. Physiological variables in blood were monitored: glucose, blood gases, mono- and divalent cations and chloride ions, osmolality, coagulation (platelet consumption, thrombin-antithrombin complexes (TAT)), and complement activation (C3a and SC5b-9), haemolysis, and leukocyte viability.
  
  
  RESULTS
  Basic glucose consumption was high. Glucose depletion resulted in successive elevation of extracellular potassium, while sodium and calcium ions decreased due to inhibition of energy-requiring ion pumps. Addition of glucose improved ion balance but led to metabolic acidosis. To maintain a balanced physiological environment beyond 6 h, glucose and sodium hydrogen carbonate were added regularly based on analyses of glucose, pH, ions, and osmotic pressure. With these additives haemolysis was prevented for up to 72 h and leukocyte viability better preserved. Despite using non-heparinized blood, coagulation and complement activation were lower during long-term incubations compared with addition of thromboplastin and collagen.
  
  
  CONCLUSIONS
  A novel whole-blood model for studies of blood-mediated responses to a cellular transplant is presented allowing extended observations for up to 48 h and highlights the importance of stringent evaluations and adjustment of physiological conditions.
authors.affiliation: Department of Immunology, Genetics and Pathology, Clinical Immunology, The Rudbeck Laboratory, Uppsala University , Uppsala , Sweden.
authors.forename: Maria
authors.initials: M
authors.lastname: Hårdstedt
authors.forename: Susanne
authors.initials: S
authors.lastname: Lindblom
authors.forename: Jaan
authors.initials: J
authors.lastname: Hong
authors.forename: Bo
authors.initials: B
authors.lastname: Nilsson
authors.forename: Olle
authors.initials: O
authors.lastname: Korsgren
authors.forename: Gunnar
authors.initials: G
authors.lastname: Ronquist
mesh_terms: D000818:Animals; D000990:Antithrombin III / Q000737:chemistry; D001784:Blood Gas Analysis; D001786:Blood Glucose / Q000378:metabolism; D002245:Carbon Dioxide / Q000737:chemistry; D002412:Cations; D002470:Cell Survival; D017690:Cell Transplantation / Q000379:methods*; D002712:Chlorides / Q000737:chemistry; D003094:Collagen / Q000737:chemistry; D003167:Complement Activation; D005947:Glucose / Q000737:chemistry; D006461:Hemolysis; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007477:Ions; D007515:Islets of Langerhans / Q000166:cytology; D016381:Islets of Langerhans Transplantation / Q000379:methods; D007962:Leukocytes / Q000166:cytology; D009994:Osmolar Concentration; D010100:Oxygen / Q000737:chemistry; D010179:Pancreas / Q000378:metabolism; D010447:Peptide Hydrolases / Q000737:chemistry; D011817:Rabbits; D013925:Thromboplastin / Q000737:chemistry; D013997:Time Factors
chemical_list: D001786:Blood Glucose; D002412:Cations; D002712:Chlorides; D007477:Ions; C046193:antithrombin III-protease complex; D002245:Carbon Dioxide; D000990:Antithrombin III; D003094:Collagen; D013925:Thromboplastin; D010447:Peptide Hydrolases; D005947:Glucose; D010100:Oxygen
keywords: Biocompatibility; blood physiology; cell transplantation; coagulation; electrolyte homeostasis; energy metabolism; leukocytes