title: Introducing a New Experimental Islet Transplantation Model using Biomimetic Hydrogel and a Simple High Yield Islet Isolation Technique.
abstract: Islet transplantation could be an ideal alternative treatment to insulin therapy for type 1 diabetes Mellitus (T1DM). This clinical and experimental field requires a model that covers problems such as requiring a large number of functional and viable islets, the optimal transplantation site, and the prevention of islet dispersion. Hence, the methods of choice for isolation of functional islets and transplantation are crucial.
  
  
  
  The present study has introduced an experimental model that overcomes some critical issues in islet transplantation, including in situ pancreas perfusion by digestive enzymes through common bile duct. In comparison with conventional methods, we inflated the pancreas in Petri dishes with only 1 ml collagenase type XI solution, which was followed by hand-picking isolation or Ficoll gradient separation to purify the islets. Then we used a hydrogel composite in which the islets were embedded and transplanted into the peritoneal cavity of the streptozotocin-induced diabetic C57BL/6 mice.
  
  
  
  As compared to the yield of the classical methods, in our modified technique, the mean yield of isolation was about 130-200 viable islets/mouse pancreas. In vitro glucose-mediated insulin secretion assay indicated an appropriate response in isolated islets. In addition, data from in vivo experiments revealed that the allograft remarkably maintained blood glucose levels under 400 mg/dl and hydrogel composite prevents the passage of immune cells.
  
  
  
  In the model presented here, the rapid islet isolation technique and the application of biomimetic hydrogel wrapping of islets could facilitate islet transplantation procedures.
authors.affiliation: Department of Immunology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.|Immunology Research Center (IRC), Iran University of Medical Sciences, Tehran, Iran.
authors.forename: Jamal
authors.initials: J
authors.lastname: Mohammadi Ayenehdeh
authors.affiliation: Immunology Research Center (IRC), Iran University of Medical Sciences, Tehran, Iran.|Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Bahareh
authors.initials: B
authors.lastname: Niknam
authors.affiliation: Department of Immunology, School of Medicine, Tehran, Shahid Beheshti University of Medical Sciences, Iran.
authors.forename: Seyed Mahmoud
authors.initials: SM
authors.lastname: Hashemi
authors.affiliation: Immunology Research Center (IRC), Iran University of Medical Sciences, Tehran, Iran.
authors.forename: Hossein
authors.initials: H
authors.lastname: Rahavi
authors.affiliation: Department of Immunology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.|Research Center for Immunodeficiencies, Tehran University of Medical Sciences, Children's Medical Center, Tehran, Iran.|Universal Scientific Education and Research Network (USERN), Tehran, Iran.
authors.forename: Nima
authors.initials: N
authors.lastname: Rezaei
authors.affiliation: Department of Stem Cell Biology, Stem Cell Technology Research Center, Tehran, Iran.
authors.forename: Masoud
authors.initials: M
authors.lastname: Soleimani
authors.affiliation: Immunology Research Center (IRC), Iran University of Medical Sciences, Tehran, Iran.
authors.forename: Nader
authors.initials: N
authors.lastname: Tajik
mesh_terms: D000818:Animals; D040761:Biomimetic Materials / Q000494:pharmacology*; D001786:Blood Glucose; D005362:Ficoll; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate / Q000494:pharmacology*; D007328:Insulin / Q000378:metabolism; D000078790:Insulin Secretion; D007515:Islets of Langerhans / Q000187:drug effects / Q000473:pathology; D016381:Islets of Langerhans Transplantation / Q000379:methods*; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL
chemical_list: D001786:Blood Glucose; D007328:Insulin; D005362:Ficoll; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate
keywords: Islet pancreas; Isolation; Transplantation; Type 1 diabetes mellitus