title: A new rat model for orthotopic abdominal wall allotransplantation.
abstract: BACKGROUND
  Abdominal wall, one of the most commonly transplanted composite tissues, is less researched and lacking animal models. Its clinical necessities were emphasized in multiple case series to reconstruct large abdominal defects. Previous animal models have only studied components of the abdominal wall transplant. We describe findings from a new model that more likely reflect clinical transplantation.
  
  
  METHODS
  Full-thickness hemiabdominal wall flap was procured from Brown Norway (BN) rats and transplanted to an orthotopic defect on Lewis rats. Three groups were studied: group 1: Lewis to Lewis syngeneic; group 2: BN to Lewis control; and group 3: BN to Lewis with postoperative cyclosporine. Vascular imaging and cross vessel section were performed along with full-thickness abdominal wall. Immune cell profiling with flow cytometry at different time points was studied in all groups.
  
  
  RESULTS
  Syngeneic group had no rejection. Control group consistently showed rejection around postoperative day 6. With cyclosporine treatment, however, transplant and recipient tissue integration was observed. Flow cytometry revealed that innate immunity is responsible for the initial inflammatory events following abdominal wall engraftment. Adaptive immunity cells, specifically interferon-γ-producing T helper (Th) 1 and interleukin-17-producing Th17 cells, dramatically and positively correlate with rejection progression of abdominal wall transplants.
  
  
  CONCLUSIONS
  Technical, histological, and immunological aspects of a new rat model are described. These results give clues to what occurs in human abdominal wall transplantation. In addition, Th1, a proinflammatory cell, was found to be a potential biomarker for allograft rejection.
authors.affiliation: Center for Vascularized Composite Allotransplantation, Chang Gung Memorial Hospital, Taoyuan, Taiwan; Department of Plastic and Reconstructive Surgery, Medical College of Wisconsin, Milwaukee, Wisc.; Department of Plastic and Reconstructive Surgery, Pontifical Catholic University of Chile, Santiago, Chile; Center for Vascularized Composite Allotransplantation, Department of Plastic Surgery, Chang Gung Memorial Hospital, Taoyuan, Taiwan; and College of Medicine, Chang Gung University, Taoyuan, Taiwan.
authors.forename: William W
authors.initials: WW
authors.lastname: Lao
authors.affiliation: Center for Vascularized Composite Allotransplantation, Chang Gung Memorial Hospital, Taoyuan, Taiwan; Department of Plastic and Reconstructive Surgery, Medical College of Wisconsin, Milwaukee, Wisc.; Department of Plastic and Reconstructive Surgery, Pontifical Catholic University of Chile, Santiago, Chile; Center for Vascularized Composite Allotransplantation, Department of Plastic Surgery, Chang Gung Memorial Hospital, Taoyuan, Taiwan; and College of Medicine, Chang Gung University, Taoyuan, Taiwan.
authors.forename: Yen-Ling
authors.initials: YL
authors.lastname: Wang
authors.affiliation: Center for Vascularized Composite Allotransplantation, Chang Gung Memorial Hospital, Taoyuan, Taiwan; Department of Plastic and Reconstructive Surgery, Medical College of Wisconsin, Milwaukee, Wisc.; Department of Plastic and Reconstructive Surgery, Pontifical Catholic University of Chile, Santiago, Chile; Center for Vascularized Composite Allotransplantation, Department of Plastic Surgery, Chang Gung Memorial Hospital, Taoyuan, Taiwan; and College of Medicine, Chang Gung University, Taoyuan, Taiwan.
authors.forename: Alejandro E
authors.initials: AE
authors.lastname: Ramirez
authors.affiliation: Center for Vascularized Composite Allotransplantation, Chang Gung Memorial Hospital, Taoyuan, Taiwan; Department of Plastic and Reconstructive Surgery, Medical College of Wisconsin, Milwaukee, Wisc.; Department of Plastic and Reconstructive Surgery, Pontifical Catholic University of Chile, Santiago, Chile; Center for Vascularized Composite Allotransplantation, Department of Plastic Surgery, Chang Gung Memorial Hospital, Taoyuan, Taiwan; and College of Medicine, Chang Gung University, Taoyuan, Taiwan.
authors.forename: Hui-Yun
authors.initials: HY
authors.lastname: Cheng
authors.affiliation: Center for Vascularized Composite Allotransplantation, Chang Gung Memorial Hospital, Taoyuan, Taiwan; Department of Plastic and Reconstructive Surgery, Medical College of Wisconsin, Milwaukee, Wisc.; Department of Plastic and Reconstructive Surgery, Pontifical Catholic University of Chile, Santiago, Chile; Center for Vascularized Composite Allotransplantation, Department of Plastic Surgery, Chang Gung Memorial Hospital, Taoyuan, Taiwan; and College of Medicine, Chang Gung University, Taoyuan, Taiwan.
authors.forename: Fu-Chan
authors.initials: FC
authors.lastname: Wei