title: Endothelial cell chimerism does not influence allograft tolerance in liver transplant patients after withdrawal of immunosuppression.
abstract: BACKGROUND
  Human liver allografts sometimes show self-induced permanent tolerance without immunosuppression. It has recently been proposed that the replacement of liver donor endothelial cells by recipient cells could confer a survival advantage. The aim of this study was to analyze liver endothelial cell replacement in relation to the response (tolerance or rejection) after withdrawal of immunosuppression in liver transplant patients.
  
  
  METHODS
  Nine liver recipient patients were entered into a program of immunosuppressive drug withdrawal. The authors studied liver endothelial cell chimerism in five of these patients who received a liver from a donor of the opposite sex by in situ hybridization for X and Y chromosomes.
  
  
  RESULTS
  Three patients (33%) achieved complete withdrawal of immunosuppression. The authors' data show similar endothelial cell chimerism in both the tolerant and nontolerant patients analyzed.
  
  
  CONCLUSIONS
  Endothelial cell chimerism has nothing to do with the induction of clinical tolerance in liver transplant patients after withdrawal of immunosuppression.
authors.affiliation: Transplant Unit, Department of Surgery, University Hospital Virgen de la Arrixaca, Ctra. Madrid-Cartagena s/n, El Palmar, 30120-Murcia, Spain. japons@mixmail.com
authors.forename: José A
authors.initials: JA
authors.lastname: Pons
authors.forename: José
authors.initials: J
authors.lastname: Yélamos
authors.forename: Pablo
authors.initials: P
authors.lastname: Ramírez
authors.forename: María
authors.initials: M
authors.lastname: Oliver-Bonet
authors.forename: Alicia
authors.initials: A
authors.lastname: Sánchez
authors.forename: Manolo
authors.initials: M
authors.lastname: Rodríguez-Gago
authors.forename: Joaquima
authors.initials: J
authors.lastname: Navarro
authors.forename: Juan
authors.initials: J
authors.lastname: Bermejo
authors.forename: Ricardo
authors.initials: R
authors.lastname: Robles
authors.forename: Pascual
authors.initials: P
authors.lastname: Parrilla
mesh_terms: D000328:Adult; D016572:Cyclosporine / Q000008:administration & dosage*; D004730:Endothelium, Vascular / Q000473:pathology*; D005260:Female; D006801:Humans; D007166:Immunosuppressive Agents / Q000008:administration & dosage*; D008102:Liver Circulation; D016031:Liver Transplantation / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D018183:Transplantation Chimera; D023001:Transplantation Tolerance; D014680:Veins
chemical_list: D007166:Immunosuppressive Agents; D016572:Cyclosporine