title: Prophylactically Decontaminating Human Islet Product for Safe Clinical Application: Effective and Potent Method.
abstract: BACKGROUND
  Transplanting pancreatic islets into recipients must be safe and effective to treat Type 1 diabetes. Islet quality and quantity are important, however, the final product must also be free from microbial contamination and low endotoxin levels.
  
  
  METHODS
  This study explored a method to eliminate contamination in manufacturing islets for transplantation. A simple (single antibiotic, n=164) and refined (triple antimicrobial agents, n=279) pancreas decontaminating methods were used to test their effects on reducing the contamination rates in the islet final product. A total of 443 pancreata were processed for islet isolations. Three samples for microbial tests (Gram stain, aerobic, and anaerobic culture) were taken at pre-process (pancreas preservation), post-isolation, and post-culture. Endotoxin levels were measured only for islets considered for transplantation.
  
  
  RESULTS
  Out of 443 pancreata used for islet isolation, 79 (17.8%) showed signs of contamination in pre-process samples; 10 (2.3%) were contaminated in both pre-process and in the final product (post-isolation and post-culture) samples. Contamination rates in which pre-process and final product samples were positive for contamination was significantly lower using the refined method (refined vs. simple method: 5% vs. 20.5%, p=0.045). Identical microbial species were present in both pre-process and in the final product.
  
  
  CONCLUSIONS
  This study demonstrated that the refined method reduces the rate of contamination of the islet final product and is safe for clinical application. Moreover, it may be used as a standard method during human islet manufacturing facilitating the application of a biological license agreement from United States Food and Drug Administration.
authors.affiliation: Department of Translational Research and Cellular Therapeutics, Diabetes and Metabolism Research Institute, Beckman Research Institute of City of Hope.
authors.forename: Meirigeng
authors.initials: M
authors.lastname: Qi
authors.affiliation: Department of Translational Research and Cellular Therapeutics, Diabetes and Metabolism Research Institute, Beckman Research Institute of City of Hope.
authors.forename: Keiko
authors.initials: K
authors.lastname: Omori
authors.affiliation: Department of Translational Research and Cellular Therapeutics, Diabetes and Metabolism Research Institute, Beckman Research Institute of City of Hope.
authors.forename: Yoko
authors.initials: Y
authors.lastname: Mullen
authors.affiliation: Department of Translational Research and Cellular Therapeutics, Diabetes and Metabolism Research Institute, Beckman Research Institute of City of Hope.
authors.forename: Brian
authors.initials: B
authors.lastname: McFadden
authors.affiliation: Department of Translational Research and Cellular Therapeutics, Diabetes and Metabolism Research Institute, Beckman Research Institute of City of Hope.
authors.forename: Luis
authors.initials: L
authors.lastname: Valiente
authors.affiliation: Department of Translational Research and Cellular Therapeutics, Diabetes and Metabolism Research Institute, Beckman Research Institute of City of Hope.
authors.forename: Jemily
authors.initials: J
authors.lastname: Juan
authors.affiliation: Department of Translational Research and Cellular Therapeutics, Diabetes and Metabolism Research Institute, Beckman Research Institute of City of Hope.
authors.forename: Shiela
authors.initials: S
authors.lastname: Bilbao
authors.affiliation: Division of Clinical Pathology, Department of Pathology of City of Hope.
authors.forename: Bernard R
authors.initials: BR
authors.lastname: Tegtmeier
authors.affiliation: Department of Translational Research and Cellular Therapeutics, Diabetes and Metabolism Research Institute, Beckman Research Institute of City of Hope.
authors.forename: Donald
authors.initials: D
authors.lastname: Dafoe
authors.affiliation: Department of Translational Research and Cellular Therapeutics, Diabetes and Metabolism Research Institute, Beckman Research Institute of City of Hope.
authors.forename: Fouad
authors.initials: F
authors.lastname: Kandeel
authors.affiliation: Department of Translational Research and Cellular Therapeutics, Diabetes and Metabolism Research Institute, Beckman Research Institute of City of Hope.
authors.forename: Ismail H
authors.initials: IH
authors.lastname: Al-Abdullah