title: Xenotransplantation of porcine neonatal islets of Langerhans and Sertoli cells: a 4-year study.
abstract: OBJECTIVE
  Porcine islets of Langerhans for xenotransplantation into humans have been proposed as a solution to the shortage of human donors. Rejection is one of the main constraints. This study presents the results of a clinical trial using a novel method for transplanting and immunoprotecting porcine islets in type 1 diabetic patients.
  
  
  METHODS
  A 4-year follow up of a clinical trial involving 12 patients, with no immunosuppressive drugs at any point. Eleven age matched untransplanted diabetics served as controls.
  
  
  METHODS
  We have developed a procedure for protecting neonatal porcine islets by combining them with Sertoli cells and placing them in a novel subcutaneous autologous collagen-covered device.
  
  
  RESULTS
  In the patients in the treatment group, no complications arose and no porcine endogenous retrovirus infection was detected. Half of the patients showed a significant reduction in insulin requirements compared with both their pre transplant levels and controls, and this reduction was maintained for up to 4 years. Two patients became insulin-independent for several months. Porcine insulin was detected in three patients' sera following glucose stimulation up to 4 years post transplant. Three years post transplant, one of four devices was removed from four patients, and the presence of insulin-positive cells in the transplant was demonstrated by immunohistology in all 4 patients.
  
  
  CONCLUSIONS
  Long-term cell survival with concurrent positive effects on metabolic control are possible by this technique.
authors.affiliation: Facultad de Medicina, Universidad Nacional Autónoma de México, D.F. Mexico. rvaldes@xenomexico.org
authors.forename: Rafael A
authors.initials: RA
authors.lastname: Valdés-González
authors.forename: Luis M
authors.initials: LM
authors.lastname: Dorantes
authors.forename: G Nayely
authors.initials: GN
authors.lastname: Garibay
authors.forename: Eduardo
authors.initials: E
authors.lastname: Bracho-Blanchet
authors.forename: Armando J
authors.initials: AJ
authors.lastname: Mendez
authors.forename: Roberto
authors.initials: R
authors.lastname: Dávila-Pérez
authors.forename: Robert B
authors.initials: RB
authors.lastname: Elliott
authors.forename: Luis
authors.initials: L
authors.lastname: Terán
authors.forename: David J G
authors.initials: DJ
authors.lastname: White
mesh_terms: D000293:Adolescent; D000818:Animals; D000831:Animals, Newborn; D001786:Blood Glucose / Q000378:metabolism; D002096:C-Peptide / Q000378:metabolism; D002648:Child; D003922:Diabetes Mellitus, Type 1 / Q000097:blood / Q000378:metabolism / Q000628:therapy*; D005260:Female; D005934:Glucagon / Q000378:metabolism; D006442:Glycated Hemoglobin / Q000378:metabolism; D006084:Graft Rejection / Q000276:immunology / Q000517:prevention & control*; D006085:Graft Survival / Q000276:immunology; D006801:Humans; D007150:Immunohistochemistry; D007328:Insulin / Q000097:blood / Q000378:metabolism / Q000494:pharmacology; D016381:Islets of Langerhans Transplantation / Q000276:immunology / Q000379:methods*; D008297:Male; D012708:Sertoli Cells / Q000276:immunology / Q000637:transplantation*; D013047:Specific Pathogen-Free Organisms; D013552:Swine; D014183:Transplantation, Heterologous / Q000276:immunology / Q000379:methods*
chemical_list: D001786:Blood Glucose; D002096:C-Peptide; D005934:Glucagon; D006442:Glycated Hemoglobin; D007328:Insulin