title: Factors affecting transplant outcomes in diabetic nude mice receiving human, porcine, and nonhuman primate islets: analysis of 335 transplantations.
abstract: BACKGROUND
  In the absence of a reliable islet potency assay, nude mice (NM) transplantation is the criterion standard to assess islet quality for clinical transplantation. There are factors other than islet quality that affect the transplant outcome.
  
  
  METHODS
  Here, we analyzed the transplant outcomes in 335 NM receiving islets from human (n=103), porcine (n=205), and nonhuman primate (NHP; n=27) donors. The islets (750, 1000, and 2000 islet equivalents [IEQ]) were transplanted under the kidney capsule of streptozotocin-induced diabetic NM.
  
  
  RESULTS
  The proportion of mice that achieved normoglycemia was significantly higher in the group implanted with 2000 IEQ of human, porcine, or NHP islets (75% normoglycemic) versus groups that were implanted with 750 IEQ (7% normoglycemic) and 1000 IEQ (30% normoglycemic). In this study, we observed that the purity of porcine islet preparations (P≤0.001), islet pellet size in porcine preparations (P≤ 0.01), and mice recipient body weight for human islet preparations (P=0.013) were independently associated with successful transplant outcome. NHP islets of 1000 IEQ were sufficient to achieve normoglycemic condition (83%). An islet mass of 2000 IEQ, high islet purity, increased recipient body weight, and high islet pellet volume increased the likelihood of successful reversal of diabetes in transplanted mice. Also, higher insulin secretory status of islets at basal stimulus was associated with a reduced mouse cure rate. The cumulative incidence of graft failure was significantly greater in human islets (56.12%) compared with porcine islets (35.57%; P≤0.001).
  
  
  CONCLUSIONS
  Factors affecting NM bioassay were identified (islet mass, islet purity, pellet size, in vitro insulin secretory capability, and mouse recipient body weight) and should be considered when evaluating islet function.
authors.affiliation: Schulze Diabetes Institute, Department of Surgery, University of Minnesota, Minneapolis, MN, USA.
authors.forename: Gopalakrishnan
authors.initials: G
authors.lastname: Loganathan
authors.forename: Melanie L
authors.initials: ML
authors.lastname: Graham
authors.forename: David M
authors.initials: DM
authors.lastname: Radosevich
authors.forename: Sajjad M
authors.initials: SM
authors.lastname: Soltani
authors.forename: Mukesh
authors.initials: M
authors.lastname: Tiwari
authors.forename: Takayuki
authors.initials: T
authors.lastname: Anazawa
authors.forename: Klearchos K
authors.initials: KK
authors.lastname: Papas
authors.forename: David E R
authors.initials: DE
authors.lastname: Sutherland
authors.forename: Bernhard J
authors.initials: BJ
authors.lastname: Hering
authors.forename: A N
authors.initials: AN
authors.lastname: Balamurugan
mesh_terms: D000328:Adult; D000818:Animals; D001681:Biological Assay; D002470:Cell Survival; D003921:Diabetes Mellitus, Experimental / Q000601:surgery*; D006085:Graft Survival; D006801:Humans; D007328:Insulin / Q000378:metabolism; D007515:Islets of Langerhans / Q000166:cytology*; D016381:Islets of Langerhans Transplantation / Q000379:methods*; D008252:Macaca fascicularis; D008253:Macaca mulatta; D008297:Male; D051379:Mice; D008819:Mice, Nude; D008875:Middle Aged; D010215:Papio; D013045:Species Specificity; D013552:Swine; D014183:Transplantation, Heterologous / Q000379:methods*; D055815:Young Adult
chemical_list: D007328:Insulin